The first goal killed us. We made a mistake and mistakes get punished against these people Millwall boss Dennis Wise

Boss Wise told BBC Sport: "We had a lot of youngsters out there and I told them they should be proud of themselves.

"They've done fantastically well and if it had been 0-0 at half-time it might have been a different game."

His assistant Wilkins added: "They will learn from this and I hope these young men will experience this again."

Wise saw Cristiano Ronaldo's first-half strike as the turning point in the game.

FA CUP RECORD Millwall's Curtis Weston became the youngest FA Cup finalist ever at 17 years, 119 days - he beat Paul Allen, who was also 17 when he played for West Ham against Arsenal in 1980

"The first goal killed us. We made a mistake and mistakes get punished against these people," the player-manager added.

"It was a sloppy goal and maybe the result of some wrong information from Neil Harris, which I'm not happy about.

"The second goal was maybe not a penalty and the third was offside but we gave it a go although it would have been better if we had gone in 0-0 at half-time."

Lions striker Harris was happy with his side's effort but felt United's Premiership quality told in the end.

Perhaps the score was a bit high but I feel proud of the team, we didnt give up and Dennis Wise is a legend. From Tom Winfield Have your say on 606

"We did what we could but it was a lapse in defending just before half-time and Ruud van Nistelrooy punished us in the second half.

"He had a quiet game but scored two goals - maybe that's the gulf in class between the teams.