Manchester United assistant boss Carlos Queiroz admits Edwin van der Sar is likely to miss this weekend's clash with Derby due to a groin injury.

"He started to feel it after a couple of minutes (against Portsmouth) when he was striking the ball," Queiroz told manutd.com. "At half-time we decided there was no chance he could keep going."

Van der Sar's deputy Tomasz Kusczak came on at half-time for his 13th appearance of the season - unlucky for him as he was later sent off in the match's decisive moment.

"We accept the penalty against us," said Queiroz, after Kuszczak conceded a decisive spot-kick.

"It was a one-on-one situation and unfortunately Tomasz touched the player (Milan Baros)."