When Diego Forlan walked away from English football in the summer of 2004, he was a figure of fun whose cult status among Manchester United supporters was born out of sympathy rather than admiration.
Not for nothing was he christened Diego 'Forlorn' during a spell at Old Trafford. The Uruguayan who arrived from South America with a big reputation left as damaged goods and he may well go down as one of Sir Alex Ferguson's most disappointing signings after he famously took eight months and 27 games to score his first Manchester United goal following a £6.9 million move in January 2002.
Indeed, such was the level of his incompetence that there was general amazement when Spanish top-flight side Villarreal offered Forlan an escape route out of England, with many observers believing this misfit was destined to beat an embarrassing retreat back to his homeland in a bid to save his faltering career.
Legendary United boss Ferguson rarely releases a player before their use-by-date has expired and yet an extraordinary transformation in Forlan's career was to occur the moment he landed in Spain.
Exploding into life in sensational fashion at Villarreal, all the confidence Forlan lacked in front of goal at United began to ooze through his veins as he finished his first season as La Liga's top scorer, bagging 25 goals and earning plaudits aplenty along the way.
When he continued his heroics in the seasons that followed, Forlan's price tag hit the heights and the €21 million Atletico Madrid paid to sign him in 2007 has long looked like a bargain. Forlan was asked to fill massive boots when he was signed as a direct replacement for Liverpool-bound icon Fernando Torres, yet he has managed to plug that considerable void in the grand manner with a scoring rate to rival the best in the game.
After his stunning 32 goals in 33 games last season earned him his second top scorer's prize in the Spanish top flight, the Forlan arriving at Stamford Bridge for the Champions League clash this Wednesday is a different beast to the broken figure we remember from his Premier League days and he is relishing the challenge.
"No one had any faith in me after what happened at Manchester United, but the people who questioned me back then are not showing their faces today," begins the always cheerful Forlan, whose placid nature means he is reluctant to lash out at his critics. "Maybe I should have had a few bets on myself when I left England for Spain because the odds on me succeeding must have been high, but my faith in my own ability never disappeared. Okay, maybe my confidence was hit by the end at United, but there is always a second chance in this life.
"It was never a case that I did not feel welcome at United because the manager and the players were fantastic to me. Even the fans supported me when I was not scoring goals, but the consistency would not come for me and in the end I had to move on.
"Joining a club like Villarreal looked like a big a step down at the time, but it was the platform I needed to start my career in Europe and I don't think anyone can question my ability to perform in the top divisions now. Despite the past, I'm not going into these games against Chelsea thinking I have something to prove to English critics who said I wasn't good enough. Since leaving Manchester, everyone can look at my record and appreciate I am not the bad player they said I was at United.
"Maybe one day I will be back in England and I would not be afraid to play in the Premier League again. Liverpool and Sunderland were interested in me a couple of years ago, but I am happy in Spain." Forlan recently revealed he had the full backing of Ferguson at United until they fell out over the length of studs he was wearing in his boots and such minor details must have nagged away at the Old Trafford chief as his protégé has scored goals by the dozen in Spain.
Ferguson may have blown fortunes to sign misfits such as £28.1 million man Juan Sebastian Veron, calamity keeper Massimo Taibi and midfield flops Liam Miller and Eric Djemba Djemba, though few of his failed buys left behind more questions than Forlan.
However, this 30-year-old is returning to England at a moment with his Atletico Madrid side in the midst of a fully blown crisis, after a poor start in La Liga was not helped by a Champions League defeat against FC Porto and a home draw against Group D whipping boys, APEOL Nicosia.
Last weekend's thumping 3-0 La Liga defeat at the hands of Osasuna piled a little too much pressure on under-fire boss Abel Resino and yet Forlan is determined to apply a positive slant on the Atletico story, insisting he is as much to blame for the side's woeful form as anyone else.
"I need to improve and the same is true of my team this season," states Forlan, who missed out on last weekend's defeat as he was given time to recover from Uruguay's World Cup qualifying defeat against Argentina a few days before. "We have not started well in La Liga or the Champions League, so we have to come back and play like we did last season.
"Our start has been poor and it means we have to go into the Chelsea games with more belief than ever. That is never easy when you have setbacks like the ones we had so far, but this team have earned the right to be the Champions League and we have to make the most of our chance.
"We are all supporting our coach and it may be that one big victory changes everything for our season. If that win arrives against a very strong Chelsea side, things can turn very quickly."
One of Forlan's rare high points in his United career came as he blasted an injury-time winner against Chelsea in January 2003, but the comedy status he held by then meant few believed his strike was anything more than a brief and fortunate moment of glory. As he prepares to make his return to English shores, those still laughing at Diego Forlan are doing so at their peril.