Ferdinand was crocked by a poor challenge by Norway striker Erik Nevland less than half an hour into Sunderland's 1-0 loss at Fulham on Sunday, when he won his first start since the Black Cats' 2-1 defeat at Birmingham on October 24.

It was an opportunity for the 24-year-old to re-establish himself after falling down he pecking order since Bruce's arrival at the club.

But those hopes, and any thoughts of a January move away from the Stadium of Light, have now taken a blow.

Bruce said: "It's a nasty one for Anton.

"Nevland's body weight came down on the ankle when they went to ground and he's no chance of being ready for the weekend.

"He's got no chance for Saturday and it looks like it could be a month at least for him.

"It's disappointing for him and disappointing for me. I've tried to freshen it up a bit because I thought we needed it, but now we have Anton injured and a couple of suspensions to cope with."

Sunderland have major concerns going into Saturday's encounter with basement club Portsmouth as Kieran Richardson and Phil Bardsley are both banned for one game and George McCartney (hamstring) and John Mensah (calf) are also in the treatment room.

"I'd rate George at no better than 50-50 at the moment," said Bruce.

"I'm not ruling him out, but it's his hamstring again and we have to be careful with him.

"John Mensah has a chance of making it for the weekend.

"The physios are working hard on all of the lads; they're earning their corn."

The injury situation means Paulo Da Silva will definitely win a recall against Pompey this weekend, though it remains to be seen whether he has to play as a full-back or in the middle.

Nyron Nosworthy will be fine, despite having stitches in a head wound after the Fulham defeat.

Portsmouth welcome back former Sunderland target Younes Kaboul this weekend.

The former Spurs and Auxerre defender, one of Pompey's most reliable performers, missed last weekend's home win against Burnley because he was serving a one-match ban for receiving five yellow cards this season.