It was far from comfortable at the end but Arsenal have successfully cleared another high hurdle in their bid to win a first Premier League title in two decades.
At Tottenham on Sunday, as so often this season, it was the Gunners' innovation at set-pieces that made the crucial difference.
Set-piece coach Nicolas Jover was deservedly at the forefront of touchline celebrations as Arsenal scored twice from corners.
They required a needed a helping hand for the first, with Pierre-Emile Hojbjerg heading past his own goalkeeper, the second was clearly off the training ground as Kai Havertz nodded home.
Jover joined Mikel Arteta in leading Arsenal's celebrations after both, a rightful appreciation of his role in transforming the team's effectiveness from such situations.
They have scored more goals from set-pieces than any other Premier League side this season and the Havertz goal was their 16th from a header, equalling their Premier League record for a season.
No wonder Sky Sports co-commentator Gary Neville said: 'It's been the same Arsenal set-up all year and it's been good all year.
'He's a little nuisance that set-piece coach, but he's damn good!'
Jover, 42, has definitely become Arteta's secret weapon this season as they dare to dream of ending their long wait for title success.
He made the headlines back in October when Manchester City's Kyle Walker appeared to snub a handshake from Jover after Arsenal beat them at the Emirates.
There is history there because Jover worked in the same role for Pep Guardiola at City between 2019 and 2021, before linking up again with Arteta at Arsenal.
Now both are going up against their old employer in a gripping title race.
Berlin-born Jover began his career as a video analyst at French club Montpellier and briefly served in a similar role for the Croatia national team.
He came to England in July 2016 to work as an assistant coach to Dean Smith at Brentford and continued under Thomas Frank when the Bees were in the Championship.
His talents were recognised by Guardiola and in 2019, Jover joined City's coaching staff to work on set-pieces.
While at the Etihad, Jover worked in his first few months with Mikel Arteta, Guardiola's No 2, before he left to take the Arsenal job.
Arteta persuaded Jover to take a similar role at Arsenal in July 2021 after previous set-piece coach Andreas Georgson returned to Malmo as sporting director.
Jover established a reputation for set-piece innovation - during his two years with City, the club created 104 chances from set plays in Premier League action, leading to 16 goals.
He also improved City's record of defending opposition set-pieces, helping them reduce the percentage of goals conceded from such situation from 39 per cent in 2018-19 to just 20 per cent the following season and 19 per cent the season after.
Arsenal's set-piece effectiveness showed a similar improvement once Jover was installed at the club.
Now, in a title race of fine margins, it could mean the difference between Arsenal winning the league and City making it four-in-a-row.
Arteta was fully aware of the difference Jover could make. After poaching him from City, he said: 'I believed we needed somebody who specialised in that.
'I met him, we started to discuss how we could apply set-pieces to the open play, which is also connected, they're not two separate things, it's all connected in the game, and how we could maximise that.
'I knew Nico from before, and I asked him to come and join our project, and he's having a really strong impact on the team.'
That was evident yet again on Sunday.