Jose Bosingwa has hailed the huge mentality impact Jose Mourinho had on Porto during their historic Champions League triumph back in 2004.
After signing from fellow Portuguese side Boavista in the summer of 2003, the then 20-year-old and his Porto team-mates wrote their names into the history books by claiming the club's second-ever Champions League title.
One man in particular especially etched his name into football notoriety, and that was then youthful Porto manager Mourinho, full of the charm and arrogance needed to make it right to the very top.
And Bosingwa claims Mourinho instilled a winning mentality within the Porto team after working very intently on the psychological side of the sport.
'It was fantastic working with Mourinho, he was the best coach in the world,' the Portuguese right-back, now retired from football, told Sportsmail.
'During that time, he provided something different for us. He brought a different mentality and philosophy to training.
'He was a very psychological person, he worked loads on that side, so he made a huge difference there.'
Mourinho won huge plaudits for guiding Porto to the top of Europe's elite table during the 2003-04 campaign.
He would quickly become the centre of attention across Europe thanks to his rapid managerial emergence, and one moment in particular still vividly stands out from that season.
At Old Trafford in March 2004, Costinha netted a last-minute equaliser against Sir Alex Ferguson's dominant Manchester United to send Porto through to the quarter-finals of the Champions League on away goals.
As the ball nestled into the back of the net in Manchester, Mourinho flamboyantly celebrated the all-important goal by sprinting down the touchline to celebrate with his triumphant players while throwing his fists into the air.
The charismatic Portuguese coach had travelled to Ferguson's own backyard and managed to steal every single headline as Porto made huge inroads in Europe.
And Bosingwa, reflecting on arguably the most memorable moment in Champions League history, has revealed the Porto players couldn't quite believe Mourinho's dramatic actions.
The 37-year-old added: 'I remember that, we were like what is he doing?
'It was a very special moment because it was a hard game against a great team and to score in the last minute at Old Trafford was very special.'
After guiding Porto to the most prestigious trophy in European football by beating Monaco in the final, Mourinho was immediately poached by Chelsea under the ownership of Russian billionaire Roman Abramovich.
He further made a name for himself when he labelled himself the 'Special One' during his Stamford Bridge unveiling.
The former Portugal international, who would move to Chelsea in 2008 from Porto, claimed he always knew Mourinho would have a massive future at the top echelon's of the managerial world.
'He was a hugely motivational coach, I always knew he would go on to do a great job anywhere he went,' Bosingwa added.
'He was and is still one of the best coaches in the world and you can see that at Tottenham. In four games, he has won three of them.
'His impact will always be positive, he always brings different things for the players and the club.'
Nissan are proud partners of the UEFA Champions League. UEFA ambassador Jose Bosingwa attended the Glyn Hopkin Nissan St Albans leg of the UEFA Champions League Trophy Tour, driven by the next generation Nissan Juke, on Saturday 7th December – click here to find out more about the Nissan Juke.