MART POOM has a fight on his hands when he returns to fitness following his knee operation.

Sunderland's Estonian keeper went under the knife yesterday as he sought to rectify a cartilage problem that led to him pulling out of Monday's night's 1-0 victory over Rotherham.

Poom anticipates being on the sidelines for at least four weeks, plenty of time for his replacement Thomas Myhre to stake a claim for the number one shirt on a permanent basis.

The Norwegian international preserved the Black Cats' lead against the bottom-of-the-table Millers at Millmoor, making an excellent low save from substitute Richie Barker after Dean Whitehead had put the Wearsiders 1-0 up.

And with at least five games between now and his predicted recovery, presuming all goes to plan, Poom realises he might not walk straight back into a team currently riding high in sixth place in the Championship.

"Thomas is a quality international keeper and he'll do a great job for the team, as he did on Monday," he said.

"Having Thomas, as well as Ben Alnwick and Michael Ingham, was a big reason why the gaffer thought it would be best for me to have the operation straight away.

"I will have to fight for my place when I am fit, I'm sure. The lads are on a great run and I don't see any reason why they can't continue. When I come back I am sure we'll still be up there challenging for the automatic promotion places."

Poom could have played against Ronnie Moore's men on Monday but would have risked exacerbating the injury and it was decided to err on the side of caution.

"I've had a sore knee since the Derby game earlier this month. I thought it was just a knock or a twist and it seemed to settle down, so I was happy to keep playing," Poom said.

"But it got worse over the weekend and I travelled to Rotherham with the squad on Monday so that I could visit the specialist in Bradford.

"He said it was best to go and have an operation. He said if it goes well then I could be back in three or four weeks, but it could be a little longer. The main thing is to get the problem resolved and make sure I'm fully fit before coming back."

Meanwhile, Michael Bridges marked his first start for Sunderland since moving to Leeds five years ago with a goal in last night's 2-2 Premiership Reserve League draw with Wolves at Durham City.

The 26-year-old striker, plagued by injuries for the last two years, showed he still has an eye for goal and should prove a valuable asset to manager Mick McCarthy in the bid for promotion to the Premiership.

Bridges opened the scoring in the 15th minute after being sent clear by Sean Thornton and in the next minute turned goal provider.

He centred from the right for strike partner Chris Brown to deceive Matt Murray, the Wolves keeper, who allowed the ball to slip from his grasp and roll agonisingly over the line.

Wolves refused to accept defeat and pulled a goal back in the 28th minute through Leon Clarke.

They then equalised on the hour when Mark Davies ran at the home defence before hitting a low drive from outside the penalty area into the bottom corner of the net.

John Oster had a goal disallowed for offside in the 69th minute then a spectacular volley from Bridges flashed just over the bar.

Sunderland: Alnwick, Lynch, Dodds, Collins, Christensen, Leadbitter, Oster, Thornton, Brown, Bridges, Dickman,

Read more about Sunderland here.