Roy Keane (Manchester United)

There was a real danger Manchester United would lose their fearless captain just after their treble triumph in 1999.
Only two months after that night in Barcelona, the United board were reportedly ready to put the midfielder up for sale before the final season of his contract began. Keane was valued somewhere in the region of £20m, with he and the club reportedly way off an agreement as the clocked ticked down to the start of the 1999/00 season.
Keane was said to be earning around £19,000 a week and had been offered around £28,000 a week.. Aware of his importance to Ferguson and the squad, Keane wanted closer to £50,000-a-week and he said he would be willing to go abroad if it meant earning the type of salary he felt he deserved: "Being a realist, I know it may have to happen," he said in his autobiography.
In early December, only 23 days before he would be allowed to speak to the likes of Bayern Munich and Juventus, it was announced that a deal had been agreed, United breaking their wage structure to accommodate Keane.
The row was re-ignited only a few months later, however, when United sent a letter to season ticket holders explaining that the only way they could afford the hike in players' wages - naming Keane in the process - was to increase ticket prices. Keane did not take it well: "It was a stupid mistake, a bad public relations exercise and something that should never have happened. I'm still waiting for my apology but I could be waiting a long time."

Steve McManaman (Liverpool)
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The Liverpool winger became the first English player to cash in on the Bosman ruling when he joined Real Madrid in 1999.
McManaman and the Reds had been in discussions over a new deal for the previous couple of seasons, though it seemed clear from very early on that the England international would ultimately be lured abroad at the end of his existing Anfield deal. Liverpool, fearing they would lose the academy graduate for nothing, accepted a £12m offer from Barcelona in August 1997, but the Catalans opted to sign Rivaldo instead and McManaman returned to Merseyside.
He did eventually move to Real Madrid in 1999, saying in the Spanish capital for four years and winning two La Liga and two Champions League titles along the way.

Ashley Cole (Arsenal)
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"When I heard Jonathan [Barnett, Cole's then-agent] repeat the figure of £55k, I nearly swerved off the road. I was so incensed. I was trembling with anger. I couldn't believe what I'd heard."
In Cole's Autobiography 'My Defence', the England defender told his version of events after a series of contract disputes that eventually led to a move across London from Arsenal to Chelsea in the summer of 2006.
But the writing was on the wall 18 months previously, when Cole had been caught meeting Chelsea and Jose Mourinho behind Arsenal's back. Chelsea, Mourinho and Cole were all fined by the Premier League, and though the player signed a one-year extension at the club, a year later Cole was gone, signing a £90,000-a-week deal at Stamford Bridge.

Sol Campbell (Tottenham)
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Campbell eventually left boyhood side Tottenham, aged 27, after rejecting an offer that would have made him the highest-paid player in the club's history. According to Spurs, Campbell "demanded a £20million three-year deal including a clause that he can walk away from the club as a free agent if we fail to achieve a Champions League place by the end of next season".
Until Tottenham revealed those demands, it seemed likely that Campbell would move abroad having become exasperated. "I had muppets as team-mates who were on treble the money", he said in his autobiography. But Tottenham's loose lips "hurt" Campbell and opened his mind to an approach from north London rivals Arsenal.
Campbell last year apologised to Spurs fans: "I'm sorry about the situation with me going and I'm sorry how it happened. I'm not going to apologise for the move [to Arsenal] because I was very successful. I'm sorry about the hurt it inflicted on them."

Wayne Rooney (Manchester United)
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Rooney’s first saga came in 2010, and though it lasted barely a week, it sent shockwaves throughout English football. The public were first made aware of a problem in the Sunday Mirror on October 17, with the paper reporting that Rooney wanted out. That story was confirmed the following day, before a "dumbfounded" Sir Alex Ferguson faced the press to give his version of events on the Tuesday.
Rooney further enraged United fans by issuing a statement shortly before the kick-off of a Champions League clash with Bursaspor to claim that United "did not give me any of the assurances I was seeking about the future squad".
There seemed no way back for Rooney and United, with Manchester City and Chelsea both reportedly interested. Angry United fans protested outside his home during the early hours of Friday, but just hours later Ferguson and Rooney stunned everyone again by shaking hands on a five-year deal.
Rooney was at it again three years later. Ferguson, after his final home game in charge of United, dropped the bombshell that Rooney had asked for a transfer. Months later, with United faltering badly under David Moyes, a deal reportedly worth around £300,000-a-week was put on the table and the England striker signed up for five-and-a-half more years.
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