Manchester United boss Sir Alex Ferguson believes Paul Scholes and Ryan Giggs could play into their 40s.
Both veterans have kicked off the new season in fine form.
Ferguson said: "We have a few of those who have lived their lives the right way, looked after themselves and been good professionals.
"You can, if you look after yourselves, have a long career in the game.
"Frank McLintock played until he was 39 and we have Ryan Giggs. But he is playing for Manchester United and the intensity of our games is enormous.
"Every game we play is a cup final - you cannot overstate that.
"Paolo Maldini was like that, unbelievable. He was 40 when he finished. Costacurta was another one.
"It can be done. It depends on how much Giggs and Scholes enjoy it and whether they stay clear of injuries."
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