Manchester United boss Sir Alex Ferguson hailed Ryan Giggs after the veteran midfielder netted on the eve of his 36th birthday to inflict defeat on Avram Grant in his first match in charge of Portsmouth.

Giggs scored his 100th Premier League goal during the 4-1 win at Fratton Park, with Wayne Rooney grabbing a hat-trick including two penalties.

With Giggs turning 36 on Sunday, Ferguson said: "He's an exceptional player. A rarity. He will play for two years yet.

"Happy Birthday. He's had it 36 times in his life, wait until he gets to 67. I think he'll be retired by then."

Pompey's goal came from the penalty spot, with Kevin-Prince Boateng scoring, although an offence did not seem apparent when Mike Dean pointed to the spot. Replays suggested Nemanja Vidic tugged Frederic Piquionne's shirt.

"The linesman has put the referee under terrible pressure and he has to listen to the linesman who is 50 yards away," Ferguson said.

"You see these things every weekend in the penalty box. If you are saying everyone who wrestles at a corner or tugs at a jersey concedes a penalty kick then that that's fine. But it doesn't happen that way and this linesman has changed the whole course of normal decision making.

"So it was a very disappointing result for us to get a penalty against us in that situation. Half-time came at a good time for us and the important thing was to keep our discipline and composure and play our football."

Rooney earned the first penalty, then Giggs set up his second and earned the penalty for the England striker's hat-trick.

"With strikers you always want them to score, he's got the matchball which is nice," Ferguson said.

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