Scouts from Brian Clough's Nottingham Forest took note of his talents and promptly signed him for the sum of £20,000. Keane was quick to impress at Nottingham Forest, making his professional league debut against Liverpool.
In 1991, Keane was a regular in the side, displacing the English international midfield player Steve Hodge, and scored three goals during a run to that season's FA Cup final, which Forest ultimately lost to Tottenham Hotspur.
A year later Keane returned to Wembley with Forest for the League Cup final but again finished on the losing side as Manchester United gained a 1-0 win.
Many say if it wasn't for Forest, Roy Keane may have never made it to the big time had Brian Clough not signed him as a pro, as he went from semi-pro to one of the most sucesssful players in English football.
Manchester United and Blackburn Rovers competed to sign Keane after Nottingham Forest's relegation in 1993. Manchester United were successful, signing Keane for a then-record £3.75m transfer fee. Keane immediately went into the first team, playing in centre-midfield alongside Paul Ince.
After the retirement of Eric Cantona in 1997, Keane became team captain, although he missed most of the 1997/1998 season because of a cruciate-ligament injury, caused by an ill-timed challenge on Leeds United player Alf Inge Haaland. As Keane lay prone on the ground, Haaland stood over Keane, accusing him of feigning injury. United were top of the league at the time, but their form dropped and they finished the season without a trophy.
Keane returned, however, to captain the club to an unprecedented treble in 1999 including the FA Premier League, UEFA Champions League and FA Cup, including an inspirational display to haul his team back from two goals down during the second-legged semi-final against Juventus. In this match, Keane received a yellow card that ruled him out of the final yet he played on as valiant as ever and got his team through. As a recognition for his efforts, Keane was voted PFA Players' Player of the Year in 2000. Keane would go on to captain United to 9 major honours, making him the most successful captain in the club's illustrious history.
Although he maintains a low profile off the pitch, Keane was involved in several controversial incidents while at Manchester United. In 1995, he was sent off from an FA Cup semi-final for stamping on Gareth Southgate, for which he was suspended for three matches and fined £5,000.
In 2001, Keane played against Alf-Inge Haaland for the first time since their clash in 1998, and was sent off for a foul which left Haaland with a serious injury. Keane was banned for five matches and fined £150,000. He subsequently admitted in an autobiography that he intended "to hurt" Haaland. Haaland retired from football shortly afterwards, previously stating on his website that the cause of this was a recurring problem in his leg, rather than Keane's tackle.
In August 2002 he was fined two weeks' wages, £150,000, and suspended for three matches for elbowing Jason McAteer. This caused much controversy in the English press as Keane booked himself in for a hip operation and thus would have missed those three matches anyway.
On 5 February 2005, Keane scored his 50th goal for Manchester United in a league game against Birmingham City. His appearance in the 2005 FA Cup final (which United lost to Arsenal in a penalty shoot out) was his seventh such game, an all-time record. Keane was also picked on the FIFA 100, a list of the greatest living footballers picked by Pelé.
Keane's trophy haul with Manchester United includes: 8 Premiership titles (1993, 1994, 1996, 1997, 1999, 2000, 2001, 2003), 4 FA Cups (1994, 1996, 1999, 2004), a European Cup (1999 - though Keane missed the final through suspension) and an Intercontinental Cup (1999).
Keane was inducted into the English Football Hall of Fame in 2004 in recognition of his undoubted impact on the English league.
Most recently, his criticism of several of his fellow Manchester United players after an abject 4 – 1 defeat at the hands of Middlesbrough was deemed too damning and was subsequently pulled from transmission on United's own TV station, MUTV.
Keane is thought to have blasted Rio Ferdinand, John O'Shea, Alan Smith, Kieran Richardson and, perhaps most notably, Darren Fletcher. Keane was widely supported by Manchester United fans after the outbursts.
He had announced that he would leave United in the summer of 2006, at the end of his contract with Manchester United. Many people were expecting Keane to fulfill his dream of playing for Celtic when he parted ways with his club of 12 years. He is already training for his UEFA coaching badges.
His then-manager, Sir Alex Ferguson, had said that he wanted Keane to succeed him as manager when he retires. However, in the wake of Keane's tirade against his own teammates, Ferguson became evasive regarding Keane's prospects as a manager. In November 2005, Ferguson said "young managers come along and people say this one will be England manager or boss of this club, but two years later they're not there. It's not an easy environment to come into, I wouldn't forecast anything."
Keane unexpectedly left Manchester United on 18 November 2005, during a protracted absence from the team due to injury. He played his last competitive game for Manchester United in September 2005, which was a 0-0 against rivals Liverpool in which he sustained a broken foot after a challenge with Luis Garcia.
Keane criticised the club's pre-season trip to Portugal, branding it unprofessional — which triggered an argument with assistant coach and one-time Real Madrid manager, Carlos Queiroz. He had already stated his belief that his contract would be the last with the club and the aforementioned MUTV transmission had frosted relations still further. There had also been rumours of Ferguson threatening to strip him of club captaincy for refusing to apologise for his MUTV outburst, although some of the players concerned had publicly backed him afterwards.
Manchester United reached an agreement with Roy Keane allowing him to leave the club immediately, and offered him a testimonial in recognition of his 12½ years at Old Trafford. The club also thanked him for his major contribution as a player.
On 30 March 2006, it was announced by Manchester United that Keane's testimonial was to take place on 9 May 2006 and the game would be against Celtic. Manchester United won the testimonial, 1-0, with the only goal in the game scored by Cristiano Ronaldo. Keane played the first half with Celtic and the second half in his former role as Manchester United captain. The game attracted the largest crowd ever for a testimonial match in England.
On 14 December, the BBC reported that Keane would sign with Celtic, after agreeing to sign a contract in the region of £40,000 per week, and he officially became a Celtic player the following day. The BBC were on agency who reported that they believed his earnings were in the region of £40,000 per week [1], however Celtic manager Gordon Strachan revealed the player did not want to become an exception to the clubs £25,000 per week wage cap. Celtic Chief Executive Peter Lawwall confirmed in the same BBC report that Dermot Desmond would not require to provide any additional funding to the club for the transfer.
Keane's Celtic F.C. career began in ignominious fashion as the Glasgow giants crashed to a 2-1 defeat to lowly Clyde F.C. in the Scottish Cup third round on 8 January 2006. Keane scored his first Celtic F.C. goal a month later in a 2-1 Scottish league victory over Falkirk F.C..
The following Sunday he retained his place and played in his first Old Firm game, being accorded the man-of-the-match title as the game's best player. Celtic won the game, Maciej Zurawski having scored the only goal. Keane went on to win the Scottish Premier League title and Scottish League Cup with Celtic in his debut season for the club.
Although, Celtic's move to bring in Keane had been criticized in the beginning, he proved himself as a vital member of the midfield with his superior tackling and skilled distribution of the ball.
On the 12 June, 2006, Roy Keane announced his retirement from professional football on medical advice.
--Wikipedia
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