After signing Michael Owen, Manchester United boss Sir Alex Ferguson insists the transfer policy of signing players under 26 is flexible.

He told Inside United: "It's not a hard and fast rule but it's true we tend to bring in players who still have more to give - those who can develop while they're here. We like younger players and in the main i think we have done pretty well with them.

"Michael's 29 but he was on a free transfer so that falls outside the usual parameters. Nemanja Vidic was 24 when he came to the club and so was Patrice Evra.

"It's a good age because players already have some experience behind them but they haven't yet fulfilled their potential. We can develop them and help them become better.

"And we've been successful at doing that with a number of players - Rooney and Ronaldo and terrific examples of that. Ji-Sung Park too- he's come on a lot since he arrived at United.

"There's not a black and white policy but we're definitely conscious of the age factor and we like players who still have room to improve."

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