SUNDERLAND winger Matt Piper is confident his injury nightmare is finally over, despite being ruled out of action until October after undergoing his fourth operation since joining the Black Cats.

Piper made just four League starts last season because of knee problems.

The 22-year-old, who cost Sunderland £3.5m when he signed from Leicester in August 2002, visited renowned knee specialist Dr Richard Steadman in America last week in a final attempt to clear up his long-standing problem.

Steadman, who has performed career-saving surgery on both Alan Shearer and Craig Bellamy, made an initial investigation of Piper's knee that revealed four significant problems.

It was originally feared the midfielder would be ruled out for the whole of next season but, following last week's surgery, Sunderland are hopeful of having Piper back in action by early October.

"I've been told I'm looking at about four months for a comeback," said Piper, who has only managed a total of 13 starts during his 22 months on Wearside.

"Dr Steadman has said that there should be no more problems after that, which is brilliant for me if you consider my problems in recent years.

"Things looked a lot more bleak after the initial investigation. I had an X-ray and an MRI scan and he told me there were three or four problems with the knee.

"He said he needed to do what's called a microfracture procedure and, at that stage, I was looking at being out for eight or nine months and being on crutches for the first three. It was bad news.

"But I was in surgery for 35 minutes and there was some good news when I came round.

"Dr Steadman is known as one of the top men for knee problems. When he told me I'd be back in around four months it filled me with confidence. The last couple of years have been a nightmare."

Piper had only just recovered from knee ligament damage when he strained a cruciate ligament on reserve-team duty last September.

He recovered to make a handful of appearances towards the end of the campaign, but suffered a recurrence that forced the latest bout of surgery.

Piper will spend next week undergoing an intensive rehabilitation programme at Lilleshall's National Sports Centre.

"He (Steadman) wants me to do leg strengthening straightaway," said the winger. "He considers the rehab to be just as important as the surgery itself.

"I was straight into training when I got back from America and I'll work over the summer."

With Piper set to miss the first two months of the season, and John Oster's future still far from certain, Mick McCarthy has lined up a swoop for highly-rated Mansfield midfielder Liam Lawrence.

The 22-year-old is out of contract and, following Monday's play-off final defeat to Huddersfield, Mansfield are resigned to losing their leading play-maker.

Lawrence almost joined Rotherham last season before the Millers balked at a proposed £150,000 fee.

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