SIR ALEX FERGUSON had words of praise for Saints' strikeforce, admitting Peter Crouch and Henri Camara had been a serious worry.

But the Manchester United manager praised the way his defence - which hasn't conceded a goal in five FA Cup ties this season - dealt with the duo's contrasting talents.

He said: "Crouch and Camara are a real handful. It's not easy - they will always give you problems. I was pleased with the way we handled them."

Ferguson admitted his team's early goal after just 86 seconds had been crucial in settling the outcome of the tie.

He said: "We have got the perfect start. That decided the game. We scored at crucial moments for us.

"It was a steady performance and showed a lot of maturity. Wayne Rooney was fantastic - his energy and desire."

Ferguson also repeated his desire for inspirational skipper Roy Keane - who scored United's opener - to keep playing for as long as possible.

He added: "I hope there is someone who can replace him. But he looks after himself and with his desire he can be here for a while."

United, meanwhile, have promised action against the fan that threw a lighted flare onto the pitch.

After Paul Scholes made it 3-0 in the 47th minute, a bright flare appeared from the away end and it landed only about ten yards from Saints goalkeeper Paul Smith.

The restart had to be delayed until the flare went out and it was removed from the pitch.

A Manchester United statement said: "The club strongly hopes TV evidence will enable him to be identified.

"United will then take swift action to make sure he will not be able to stain the club's reputation in such a way again."