He arrived in the summer of 2000 from Monaco as a World Cup and European Championship winner with the French national team. Such success had many people predicting that the Red Devils had landed their successor for the Dane, following the failed attempts of Mark Bosnich and Massimo Taibi.
Despite his eccentric style, the keeper initially took to life with the champions positively. However, there was an example of the errors that would ultimately end his time with the club during West Ham United's visit in the FA Cup 13 years ago today. The Hammers had not won at Old Trafford since 1986 when goals from Ray Stewart and Geoff Pike sealed a 2-0 victory, but Barthez helped to ensure that the negative run ceased.
It had been anticipated that Sir Alex Ferguson's United would ease into round five, particularly because a number of the visiting players, including Frederic Kanoute and Shaka Hislop, were carrying injuries.
Yet, just as a replay looked inevitable, Barthez and Paolo Di Canio took centre stage with 14 minutes left to play. A through-ball from Kanoute released Di Canio, who the United keeper believed was in an offside position. He continued his appeal as the Italian bore down on his goal, only reacting in time to see the frontman slot a low effort beyond his reach.
Ferguson responded by throwing Ole Gunnar Solskjaer and Dwight Yorke into the action, but it was a case of too little too late as the Londoners held out to seal their spot in the fifth round of the competition at the home side's expense.
Speaking about that tie-winning incident after the final whistle, West Ham boss Harry Redknapp said: "You wouldn't want anyone in that position other than Paolo."
MAN UNITED: Barthez; Irwin, Silvestre, Stam, G Neville; Beckham, Keane, Butt, Giggs; Sheringham, Cole
WEST HAM: Hislop; Tihinen, S Pearce, Dailly, Schemmel Winterburn; Lampard, Cole, Carrick; Kanoute, Di Canio