SUNDERLAND are facing a looming midfield crisis after Sean Thornton's sending-off in the 3-1 thumping at Stoke.

The Republic of Ireland Under-21 international received a second yellow card when he committed another foul on former Middlesbrough loanee John Eustace in a physical contest at the Britannia Stadium.

Thornton, an influential figure in Sunderland's recent revival, is now set to sit out a one-match suspension for the home game against struggling Ipswich a week on Tuesday.

Black Cats manager Mick McCarthy is also anxious to see Paul Thirlwell avoid any further disciplinary problems after the stand-in skipper picked up his fourth booking of the season.

With Thirlwell only a yellow card away from a one-game ban and club captain Jason McAteer facing another lengthy spell on the sidelines with a recurrence of hamstring trouble, McCarthy will be grateful for the versatility of Colin Healy.

The Irish international, signed last month on a free transfer from Celtic, started his first Sunderland game at Stoke, where he was pressed into emergency right-back duties because of injuries to Stephen Wright and Darren Williams.

But Healy is likely to be asked to switch to a more accustomed midfield role in the near future as Sunderland feel the effects of the drastic reduction in playing staff following relegation last season.

McCarthy also signed Jeff Whitley on a free in the summer, but the former Manchester City midfielder has so far failed to impress and made only one appearance.

"Colin slotted in at right-back for us, but I don't worry about him because he can play anywhere,'' said McCarthy. "He's a very good player.

"It comes in very handy when you have someone like Colin who can play a variety of positions.

"When I was in charge of the Irish team, we had him wide right and he played right-back in the Under-21s. He's a central midfield player, but he's comfortable wherever he plays.''

Despite the threat of suspension, Thirlwell is not in the mood to curb his combative approach, and he urged his teammates to make lowly Derby suffer for Tuesday's setback when Sunderland visit Pride Park on Saturday.

"We'll have to bounce back at Derby,'' said Thirlwell, after the Black Cats' four-match winning run had come to an abrupt end.

"The good thing about this league is that the games come thick and fast, so there's no time for us to dwell on things and feel sorry for ourselves.

"We've been playing some good football recently, but first of all we've been winning the battles. We didn't do that against Stoke, so we'll go to Derby and try to rectify things.

"It was pretty disappointing the other night. That 15-minute spell in the first half, when they got their three goals, left us a mountain to climb and cost us the match.

"But this defeat won't knock the confidence in the side, because we know we're better than that.''

Sunderland were hit by another injury blow when centre-back Gary Breen, outstanding since his arrival on a free from West Ham, sustained a groin strain which forced him to be replaced by Joachim Bjorklund at half-time.

Breen's failure to signal his distress sooner brought a mild rebuke from McCarthy, who said: "He picked it up in the first half and he should have come off earlier.

"I wish I'd known he was suffering, because I would have got Jocky on.''

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