Owen Hargreaves, the former great hope at United, has crossed Manchester with a 'chip on his shoulder'.
The 'English Patient' has a point to prove with Manchester City
Is there a more depressing sight than a player returning from a long-term injury, only to break down again in full view of the many thousands wishing him well?
Owen Hargreaves was a surprise choice in the starting XI for Manchester United against Wolverhampton Wanderers last November, but a buzz went around Old Trafford that he was back.
He was warmly applauded, yet the high was short-lived. Hargreaves lasted just five minutes before signalling to the United bench that he could not continue.
United fans liked Hargreaves, the midfielder who signed from Bayern Munich in 2007, and settled straight into a team which would win the English Premier League and Champions League in his first season.
There had been worries about his injury record in Bavaria where he was nicknamed "The English Patient", but Hargreaves had also won four Bundesliga titles and the 2001 Champions League, in which he effectively anchored Bayern's midfield alongside their peerless captain, Stefan Effenberg, against Valencia in the final.
After Steve McManaman for Real Madrid a year earlier, Hargreaves became only the second English player to win the European Cup with a non-English team, in a glorious first season at Bayern.
He was capped by England for the first time that year, and would be the gem in the middle of England's 2006 World Cup campaign.
A midfielder of such class in his prime cost United £17 million (Dh101.6m) and the Canadian-born player, who has a Welsh mother and an English father, made 23 starts and 11 more appearances from the bench in his first season in England.
To underline his versatility and the esteem in which Sir Alex Ferguson, the United manager, held him, Hargreaves started the 2008 Champions League final against Chelsea on the right of midfield rather than in his usual role as a defensive midfielder.
That meant Park Ji-sung was left out of the squad, a decision Ferguson described as one of the most difficult he has ever had to make.
Hargreaves played all 120 minutes, and also held his nerve to score United's fourth penalty in the shoot-out.
The conversion was vital as Cristiano Ronaldo had missed the third penalty and Chelsea had netted all of theirs.
Had Hargreaves not have scored and Cole scored their fourth (as he did), Chelsea would have been crowned European champions for the first time.
A recurring patellar tendinitis problem restricted Hargreaves to just two games the following season, and a token one minute substitute appearance in the final game of 2009/10.
By then, Hargreaves had seen several specialists including the renowned knee surgeon, Richard Steadman - with conflicting reports of his progress.
It was understood that United's view of his injury did not always tally with those treating Hargreaves, but the midfielder continued to maintain that he was on his way back.
Last November, he made that solitary five minute cameo against Wolves before pulling his hamstring after attempting a low cross. Hargreaves cried as he left the field on the way back to the dressing room. Ferguson used the words "disaster", "gamble" and "unbelievable" after the game.
Hargreaves would not play again for United. His contract ran out in June, and he was considered finished by many in football.
United did not offer him a new contract, not even on a pay-as-you-play deal. He had cost the club around £400,000 for each of his 26 starts and 13 substitute appearances. Ferguson's patience had run out, and he said that he wanted to bring new young players through, which he is doing.
In the one interview he gave to the Daily Mail, Hargreaves said: "I've just got this huge chip on my shoulder because I've been out for three years, and people think I'm dead and buried."
A bizarre fitness video of Hargreaves training was posted on YouTube. He looked like the Six Million Dollar Man as he sprinted and shunted, and ran at speed on a treadmill with weights attached to his legs. Backwards.
Several Premier League clubs and the Championship side Leicester City were linked with him in the summer, but no moves materialised. Then, on the eve of the transfer deadline, Hargreaves was spotted entering a hospital for a medical with Manchester City.
Manchester was stunned, football too. But Hargreaves signed a one-year deal, which is heavily incentivised according to how many games he plays.
He does not need the money, he needs to play football. His body had been battered by injury from a young age, but he told Ferguson he could play 40 games this season before leaving United.
He would be unlikely to start that many even if he was a first-choice player for City, and even half that number would be a major achievement. Time will tell if the 30 year old's optimism is justified.