MICK McCARTHY has warned Sunderland's defeated and deflated FA Cup semi-finalists to pick themselves up and ensure their primary goal of promotion to the Premiership is achieved.

The Black Cats hardly have any time to reflect on losing 1-0 to First Division rivals Millwall at Old Trafford as they face bottom club Wimbledon at Milton Keynes tomorrow night.

A disconsolate McCarthy had to face the media in the aftermath of witnessing Sunderland succumb to the Lions - ending any hopes they had of winning the world famous trophy they last lifted in 1973.

The result also assures Millwall of UEFA Cup football next season, while McCarthy's men are left wondering what might have been.

But Sunderland, sitting third in the league, take on the Dons tomorrow night knowing three points will strengthen their hand as they bid to bounce back to the top flight at the first attempt.

And McCarthy is keen for all his squad to quickly forget about their failings in Manchester and concentrate on securing promotion.

"I said to them in the dressing room that I could be lousy about it and they could be lousy about it," said McCarthy. "I've had to do all the TV, the press stuff and you have just got to face up to it.

"I'm disappointed but we can't hide away. We have to be men about it and respond. We have had disappointments already, maybe not of this magnitude, but the players have to respond and we'll find out on Tuesday what they are like.

"Semi-finals are the most painful matches to lose. If you lose in the first round then you're out of it and you can forget about it. But the longer you go in a competition then hope springs eternal and now Millwall have gone though and good luck to them."

Expectancy levels were high back in the North-East that Sunderland could reach their first final since 1992.

Successes in previous rounds against Hartlepool, Ipswich, Birmingham and Sheffield United had led to many of the club's supporters considering the prospect of playing European football next season.

However, a goal from midfielder Tim Cahill in the 25th minute yesterday was enough to ensure that Millwall earned the right to face Manchester United in Cardiff on May 22.

Prior to the goal Sunderland had their chances - most notably John Oster's free-kick which hit the bar - and Kevin Kyle and George McCartney could have levelled matters after the restart.

And McCarthy said: "Coming out of the dressing room I'm disappointed with the result, who wouldn't be?

"But I don't think my players have let anyone down. We started well but goals determine results. Goals can determine attitudes and performances as well and that's what happened.

"Millwall were better after they scored. We rallied just before half time and then in the second half we had enough chances to score at least one. They had the chances and they defended well."

Jason McAteer was sent off four minutes from the end of the pulsating Cup tie after a pull on the shirt of striker Neil Harris.

McAteer had earlier been booked for apparently trampling over Millwall skipper Kevin Muscat. That first-half incident sparked a few moments' push and shove from a number of players.

And McCarthy admits his midfielder deserved to be shown the red card.

"Jason has pulled him back so you can't argue with that," said the Sunderland chief. "But I'm not going to condemn Jason for that. I thought we should have had a free-kick beforehand but I'll have to see that again for a clearer view.

"As for the first half incident I saw it all. There were arms and legs being thrown but I'm not going to argue about what happened."

McCarthy, who started his managerial career at Millwall, also lavished praise on his opposite number Dennis Wise.

Wise, left needing stitches after a challenge with Paul Thirlwell, never stopped battling throughout the encounter.

And McCarthy said: "He's one of the rare players that can still run around at 37 and good luck to him. He's been a terrific player over the years. He's much maligned at times but not by the players who are alongside him. You love him when you play with him and you hate him if you don't."

Read more about Sunderland here.