MICK McCarthy last night insisted that his youngsters would learn a valuable lesson from the manner of last night's 2-0 defeat at Millwall.

Sunderland saw their chance of going second in the league disappear at the New Den as Millwall tasted victory over them for the fourth time in the space of just 15 months.

Meetings between these two sides are rarely games for the footballing purist and, for the second season in succession, Sunderland found themselves dragged into a war of attrition that was always going to suit the home side.

The Black Cats were already ruffled by the time Dennis Wise fired Millwall ahead with a disputed 33rd-minute penalty, and their foul mood worsened when David Livermore doubled the Lions' advantage on the stroke of half-time.

But, with all four of Sunderland's defenders under the age of 25, McCarthy refused to be too disheartened by his side's display.

"It's a learning curve for my players," said the Black Cats boss. "Some of these lads have come out of reserve teams, some of them have come from Mansfield and Oxford, and one of them has even come from Dumbarton.

"They've done really well for me, so I'm not going to be too critical about one defeat. It's a difficult place to come and play, but they'll learn from the experience.

"Millwall always provide a tough test here, but I think my players feel hard done by and they'll have to take on board what's happened.

"I thought we started extremely well and, for 30 minutes, it was a very quiet place to be. But the second goal has changed things completely - suddenly Millwall were full of running and full of confidence. They deserved the result in the end."

Millwall's second came in the 44th minute, but it was the home side's controversial opener that altered the complexion of the game.

Replacement right-back Mark Lynch tussled with midfielder Josh Simpson but, while the contact appeared to be little more than a legitimate shoulder charge, referee Andre Marriner showed no hesitation in pointing to the spot.

Even Millwall's assistant manager Ray Wilkins admitted the penalty had been "soft" but, after Sunderland had profited from a similarly disputed decision at Rotherham, McCarthy refused to point the finger at the referee.

"Ray was shaking his head more than I was on the touchline," he said. "But I'm not going to criticise the decision here, although I'll certainly be mentioning it in my referee's report.

"We had a controversial decision that went for us at Rotherham, so I suppose it's the rub of the green. Ronnie Moore was feeling sick about that decision, but this just proves that some you get and some you don't."

l Midfielder John Oster has joined Leeds United on a one-month loan. The Wales international, who has been the target of abuse from the Stadium of Light boo boys, has not started a league game since August.

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