STEVE BRUCE admits John Mensah's ongoing injury problems have been a huge frustration - but is backing the Ghana skipper to become a key player for Sunderland when fit.

Lyon defender Mensah is on a season-long loan with the Black Cats but has so far been restricted to just three outings since moving to England.

The 27-year-old has struggled with a series of minor injuries, the latest of which is a calf problem that has kept him out of action for a month.

Mensah was not in contention for this afternoon’s game against West Ham and is also likely to miss next weekend’s trip to Spurs.

But, with a free weekend coming up after the Spurs game, Bruce is hoping he will be fit by the time Sunderland resume their Premier League campaign at home to Arsenal on November 21.

“It’s tough because John has a recurrent calf problem which is not in itself serious but just something that he is trying to shake off,” said Bruce.

“He’s been close a couple of times to being fully fit and then popped it again which is a frustration because I think he is an absolutely top-class central defender.

“Hopefully he won’t be sidelined for too long because I am dying to get him out there and involved for us.

“He’s a top quality player and we hope to have him back in training over the next couple of weeks.”

Mensah made his debut for Sunderland as a substitute in the home win over Hull in mid-September and started the Carling Cup win against Birmingham at the Stadium of Light 10 days later and the league victory over Wolves on Wearside.

But his injury problems have meant he has not figured since, even on the bench.

Mensah is keen to get back to full fitness as quickly as possible as he looks to earn a permanent move to Sunderland. The Black Cats’ loan deal with Lyon includes an option to buy Mensah for a fee of around £7m at the end of the season.

Mensah is not the only Sunderland player in the treatment room at present, with Lee Cattermole (knee ligaments), Phil Bardsley (shoulder), Fraizer Campbell (hip), George McCartney (hip) and Bolo Zenden (hamstring) all picking up injuries.

Those problems have highlighted the fact that Bruce has a relatively small squad – and that is something he is ready to address in the January transfer window.

He said: “There have been a lot of changes at the club in terms of squad size and I think everyone knows we haven’t got the biggest squad right now.

“We do have options and we are fortunate to have quite a few players who can play in quite a few positions.

“But it is still a concern and something we are monitoring.”