The Champions League is back for another season as Europe's elite prepare to battle it out on the biggest stage in club football.
Manchester City are out to retain their status as European champions, while cross-city rivals United face a daunting curtain-raiser against Bayern Munich.
Arsenal return to the Champions League following a six-year absence and Newcastle rejoin the top table for the first time since 2003 as they look to qualify from the toughest group of the lot.
Meanwhile, Real Madrid are searching for a 15th European title and will be spurred on by Jude Bellingham as he prepares for his first Champions League outing at the Santiago Bernabeu.
Mail Sport analyses every team below in our ultimate guide to the Champions League group stage.
Group A - Bayern Munich, Manchester United, Copenhagen, Galatasaray
Massive names with Champions League pedigree occupy group A with Bayern Munich and Manchester United the heavy-hitters hoping to pave their way to the next round.
United are back in Europe's most prestigious cup competition and are determined to make it to the latter stages of the tournament, even if their worrying Premier League form could spell an early exit.
Bayern - led by Harry Kane - are expected to sail through the group stage and will fancy their chances of topping the pool given their history in the competition that saw them make it to the quarter-finals last year before being knocked out by Manchester City.
Erik ten Hag is under pressure for the first time in his managerial tenure at United and could find himself in an untenable position if the English giants crash out in the first round, however, they should have enough to get the better of Copenhagen and Galatasaray even if they lose to Bayern.
Reigning Danish champions Copenhagen finished bottom of their group that contained Man City and Borussia Dortmund last year, losing three matches and drawing the same amount and will be eager to get a win under their belt this time round.
Galatasaray are unbeaten in the new Turkish Superlig season and come into their opening game against Copenhagen off the back of impressive high-scoring domestic performances. They strengthened in the summer with former Premier League stars and could be a dark horse in the group.
Player to watch: Harry Kane
The England captain has appeared in the Champions League during five separate seasons with Tottenham but things feel different with him now leading the line at Bayern Munich.
Kane previously made it to the final with Spurs when they lost to Liverpool in 2019, but has otherwise been compelled to early exits from the competition during his time in London.
He's scored four goals in four Bundesliga appearances this season and has previously demonstrated his goalscoring ability in the Champions League after he previously became the fastest player to reach 20 goals in the competition in just 24 games four years ago, however, Erling Haaland has since broke that record.
Expect Kane to flourish in the group stage against beatable opponents and he should be challenging at the top of the Champions League goalscoring charts before the knockout stages.
Must-watch match: Bayern Munich v Man United - September 20
Two of the biggest teams in world football will kick-start their 2022/23 Champions League journeys at the Allianz Arena on Wednesday, September 20. United can make a statement by beating Bayern, but not losing would be a more than respectable result given their thrashing at the hands of Brighton at the weekend.
Supporters aren't happy with the club who look like they are in chaos mode both on and off the pitch, but a strong outing against one of the tournament favourites would shift the focus and dampen some of the criticism they have received.
Group B - Arsenal, Sevilla, PSV Eindhoven, Lens
Arsenal supporters have had to wait six years to be back in the Champions League but finally they have returned and expectations are high.
Mikel Arteta's side fell agonisingly short of the Premier League title last season and have started the new season strongly, although balancing competing in Europe's top club competition could bring new challenges.
The Gunners were previously Champions League regulars but consistently struggled to make it through the round of 16 as they exited at that stage in their past seven appearances. Such an exit this time round won't be accepted by supporters.
Sevilla will provide the strongest challenge for top spot in the group given their European history, however last season's Europa League winners have always looked like a team more suited to the second-tier competition instead.
PSV Eindhoven beat Arsenal in the Europa League group stage last season and would love the chance to repeat that feat again. They have enjoyed a 100 per cent winning start in the Eredivisie and are more than capable of causing an upset.
Lens are the largely unknown quantity in the group after they finished second in Ligue 1 last season, however are currently bottom of the French top-flight and without a win in five matches.
Player to watch: Bukayo Saka
There is a general consensus that the Arsenal star is made for occasions like this, and a first appearance in the Champions League will soon provide an answer.
Saka is everything you want in a modern day winger, pace, trickery, and an ability to finish, now he will get the chance to do so on the biggest stage in club football where there is no easy game.
He will be crucial to Arsenal's success in Europe and is already one of the leaders in Arteta's team despite being jut 22-years-old. He will be relishing the chance to represent his boyhood team in the Champions League and is tasked with providing key goals and assists.
Must-watch match: Arsenal v PSV - September 20
Two entertaining matches were played out by the duo in last season's Europa League group stage with both taking three points at home.
PSV and Arsenal are in strong form coming into their opening Champions League clash and both are committed to playing expansive attacking football that is entertaining and guarantees goals.
Group C - Napoli, Real Madrid, Braga, Union Berlin
Real Madrid were well-beaten by Man City in last season's Champions League semi-final and are out to prove a point as they chase down a 15th cup crown in the competition, however, Napoli could prove to be an early group stage thorn.
Carlo Ancelotti's side are the early LaLiga leaders after winning their opening five matches, scoring 10 goals and conceding just three in the process, and will again focus the majority of their efforts on winning in Europe.
Napoli dominated in Serie A last season to be crowned Italian top-flight champions and are a dangerous outfit with striker Victor Osimhen leading their attack, but have stuttered in the opening weeks of the new league campaign.
Union Berlin and Braga will want to cause an upset by making it out of the group stage but the more likely outcome is they will be left fighting for third place between themselves.
Player to watch: Jude Bellingham
Madrid's team is packed with superstars but none can rival the current form of Jude Bellingham who is making an early season claim as the best midfielder in world football.
The English talent has lit up LaLiga since joining Madrid in a £115m summer move from Borussia Dortmund and he is already looking like a bargain at that price after a series of impressive performances.
Bellingham has clinched five goals in as many league games this season and is the key cog in Madrid's goalscoring machine that now looks a complete outfit with the former Birmingham star at the heart of everything.
His impressive personal record in the competition saw Bellingham previously bag six goals during his time in Germany and he is more than capable of starring in Europe with Madrid this season.
Must-watch match: Real Madrid v Napoli - November 29
The pair will meet for the second time at Madrid's newly redeveloped Santiago Bernabeu at the end of November in the penultimate group stage clash and this match could be the decider of who tops the pool.
Group D - Inter Milan, Benfica, Salzburg, Real Sociedad
This will be one of the more closely-contested groups and there could be a situation heading into the final matches where the top two spots for the next round are still up for grabs.
Inter Milan were the surprise addition in last season's Champions League final where they fell to Man City and will be confident of making it out of the group stage again this time round.
They are the early season pacesetters in Serie A with Simone Inzaghi's side winning their opening four games including a 5-1 thrashing of rivals AC Milan at the weekend. Inter will fancy themselves to top the group.
Benfica topped a strong group containing PSG and Juventus last season and endured a successful run to the quarter-finals where they were beaten by Inter. They will be desperate to challenge for top spot again and have started the new season brightly, but have been prone to slip-up in the past.
Salzburg and Real Sociedad are formidable opponents and if they make a strong start in the Champions League will be hard to stop.
Player to watch: Lautaro Martinez
The Argentinian is the top scorer in Serie A with four goals in five games and has a good chance to get early goals in the group stages against three beatable opponents.
He's formed a strong partnership with strike partner Marcus Thuram over the summer and has the required skill to take Inter deep into the competition once again.
Must-watch game: Inter v Benfica - October 3
If Benfica and Inter are to achieve their aims of making it to the knockout stages of the Champions League then this match could prove to be difference between who finishes first and second in the group.
The pair have played each other in Europe on five separate occasions with the Portuguese outfit still without a win in the fixture.
Group E - Feyenoord, Atletico Madrid, Celtic, Lazio
Celtic are Scotland's solo representative in the Champions League but will be hard pushed to make it out of a competitive group stage in this season's competition.
Atletico Madrid suffered an embarrassing group stage exit last year after winning just one game and Diego Simeone is desperate to correct the wrongs of that early departure this time round.
They've endured a mixed start to the new season, winning just two games and sitting seventh in the league standings, but have gone deep into the latter rounds of the Champions League on multiple previous occasions.
Meanwhile, Celtic are singing at the top of the Scottish Premiership but the difference in quality between that division and the rest of Europe usually becomes clear during the group stages. Celtic finished bottom of their group last season after failing to win a game.
Lazio need to rectify a troublesome start in Italy if they want to progress to the knockout stages, while Feyenoord have began to improve in recent weeks and are fourth in the Dutch top-flight.
Player to watch: Antoine Griezmann
The France World Cup winner usually saves his best performances for the biggest stage and there are none bigger than the Champions League when it comes to club football.
Griezmann boasts beautiful technical skill and an ability to pop up with a goal in key moments when Atletico are coming under pressure.
His performances will be crucial to Atletico's success in Europe but he must be supported by his strike partner whether that is Alvaro Morata or Memphis Depay.
Must-watch match: Celtic v Lazio - October 4
The Scottish champions know how to create an atmosphere and will need every ounce of support to guide them to victory in their opening Champions League home game.
If Celtic want to stand any chance of getting out of their group then they have to win their home games and Lazio's recent form shows they are prone to making mistakes.
Group F - AC Milan, PSG, Newcastle, Borussia Dortmund
Welcome to the Champions League, Newcastle. Eddie Howe's side have been given the toughest group of them all on their induction into European competition and will need to be at their very best to stand any chance of advancing.
Paris Saint-Germain are favourites to top the group as they continue to chase an elusive Champions League crown and will be spurned on by Kylian Mbappe after the player's future was eventually sorted.
AC Milan made it to the semi-finals last season and will see Sandro Tonali return to the San Siro with Newcastle this year, but they will have to improve on recent results in Italy.
Borussia Dortmund are Champions League regulars and know how to get out of the group stage but they could find themselves bottom of the group if they don't get off to a strong start.
Newcastle supporters are just delighted to be rubbing shoulders with Europe's elite but will want to see their side compete even if they don't make it out of the group. They have endured a difficult start in the new Premier League season but if they click as they did so often last year then they can beat any of the teams in their group.
Player to watch: Alexander Isak
The Newcastle talisman has shown since he arrived at St James' Park in a club record £63m move last summer that he has all the attributes to become a world class talent. Now he has to prove that in the Champions League.
Isak boasts fearful pace and devastating dribbling skills but has to be more consistent - along with the rest of his team-mates - than what he has been in the opening weeks of the Premier League.
A goal in the first match against AC Milan would do him the world of good and there will be chances given the Italian side's recent poor defensive displays.
Must-watch match: AC Milan v Newcastle - September 19
The San Siro is one of the iconic Champions League venues and Newcastle kick-off their European journey with a trip to Italy.
This is the biggest test of Howe's managerial career to date and while he will want a win, the crucial point will be avoiding an embarrassing defeat that would be hard to recover from.
Group G - Manchester City, RB Leipzig, Crvena Zvezda, Young Boys
Pep Guardiola's side finally got the duck off their back last season as they ended their agonising wait for a first Champions League title and it would be no surprise to see them retain the cup this year.
City are already top of the Premier League after winning all five of their opening matches and will easily top their Champions League group.
The real fight will be for second place with Leipzig favourites to follow City to the knockout stages ahead of Young Boys and Serbian outfit Crvena Zvezda.
This should be a relatively predictable group with the English and German side handed the easiest group of them all.
Player to watch: Erling Haaland
City's squad is packed with so many superstars but there is only one who commands attention from every eye in the ground. Erling Haaland.
The Norwegian fired City to the Champions League title last season as he finished top scorer with 12 goals and also became only the third player in history to score five goals in a single match in the competition.
Haaland also topped the leaderboard for the most combined goals and assists in the Champions League during City's campaign and is showing no signs of slowing.
Must-watch match: Man City v RB Leipzig - November 28
It was this match in the round of 16 stage last season that Haaland bagged five goals and Leipzig will be out for revenge, even if it's unlikely they will get any.
City boosted their ranks during the summer with former Leipzig star Josko Gvardiol and he will want to make an impact for his new team against his former side.
This will be City's most competitive group stage game but still expect them to breeze past their German opposition.
Group H - Barcelona, Porto, Shakhtar Donetsk, Antwerp
The Blaugrana have returned for a second stint in the Champions League under Xavi and will have to do better than their group stage exit last season with their a strong belief in Spain that they can go all the way to the final at Wembley.
Barcelona boss Xavi guided the club to the LaLiga title last season but was left frustrated after being knocked out of Champions League and then the Europa League by Manchester United.
Featuring the likes of Robert Lewandowski, Joao Felix and Frenkie de Jong should provide them with enough quality to top the group with Porto expected to qualify in second.
Shakthar Donetsk are seasoned veterans in the competition but often struggle to make it out of the group, while Belgian side Antwerp are featuring in the competition for the first time in the club's history and it would be a huge ask of them to qualify for the knockout stages.
Player to watch: Ilkay Gundogan
He led Manchester City to the Champions League last season and has been brought to Barcelona to try and do the same.
Gundogan often thrives with big goals in big games as he did so often with City at the end of last season and he will carry huge expectation heading into the Champions League.
Must-watch match: Barcelona v Porto - November 28
Barcelona should have already qualified for the next round by the time this match comes around but if they haven't then this will be a nervy encounter.
Porto are second in the Portuguese top-flight and shouldn't be discounted as serious contenders for top spot in the group, despite Barcelona being favourites.
There is already huge pressure on the Spanish giants to deliver this year and they will want to put early distance between themselves and the rest of the group.