LIAM Lawrence has welcomed team-mate Matt Piper's long-awaited return to fitness, despite the right winger threatening to take his place in the Sunderland first team.

Piper, who has made just 12 league appearances for the Black Cats since moving from Leicester two years ago, has been plagued by a series of knee problems that had threatened to bring a premature end to his career.

But, after travelling to the US to visit renowned knee surgeon Richard Steadman in the summer, the 23-year-old has finally been able to resume competitive action in Sunderland's reserves.

His pinpoint cross led to Richie Ryan's winner against Blackburn on Tuesday night and, while Mick McCarthy will not be rushed into promoting him to the first team, Piper could be on the bench for Saturday's home game with West Ham.

His last senior outing came against Crystal Palace in April and, given his limited involvement in the last two years, Sunderland fans could be forgiven for needing a reminder of his talents.

Lawrence needs no such prompting though, as he played alongside Piper when the former Leicester winger spent two months on loan at Mansfield three seasons ago.

The pair are set to battle it out for Sunderland's right-wing berth - a tussle which Lawrence believes can only work in the Black Cats' favour.

"I've perhaps seen more of Matt Piper than some Sunderland fans," said the 22-year-old. "I played with him when he was on loan at Mansfield from Leicester City.

"When he was there he played up front, and you could see then how quick he was and what a good player he was.

"I think his position now is on the right of midfield and he will probably be competing with me for a place in the side, but I welcome that competition.

"He's a very good player who cost the club £3.5m. He's been sorely missed and while he is a threat to me in some respects, you need to have players like him fit and available."

Lawrence is currently enjoying his best run in the side since making a £125,000 switch from Mansfield this summer. He has been involved in Sunderland's last six games - four of which he has started - and grabbed three goals in the space of four days at the start of last month.

Piper's return could curtail that run but, after stepping up two divisions in the summer, the midfielder always expected his first season on Wearside to be something of a stop-start affair.

"It's been frustrating not to start every game," admitted Lawrence. "But when you come to a club like Sunderland you expect that.

"I think perhaps I was in the comfort zone at Mansfield. I could play average one week, good the next and bad the week after that, but I basically knew I was always going to be in the side.

"At Sunderland, you can play well one week and not be in the side the week after. It has been different for me, sometimes being a bit-part player, but I feel as though I belong here and I feel a part of the first team. It's up to me to prove I deserve a place in the side every week. There is competition for places in every position at this club. That's the biggest leap I've made coming here."

Lawrence's emergence has coincided with the exit of another wide player, John Oster, and the Wales international yesterday extended his loan spell at Championship rivals Leeds by a further month.

Oster has made five appearances for the Elland Road outfit since moving at the start of last month, and will now remain in West Yorkshire until January 3.

He will, however, be ineligible when the two sides meet at the Stadium of Light on Boxing Day.

McCarthy has confirmed he is ready to off-load Oster for good, but is reluctant to lose money on a player who cost the Black Cats £1m five years ago.

Leeds' boss Kevin Blackwell is willing to pay the going rate, but his hands are tied until the club's board complete their protracted takeover talks with two consortia hoping to buy the financially-stricken outfit.

* Goalkeeper Mart Poom has suffered an injury setback as he recovers from knee surgery.

The Estonian international returned to training on Monday, but complained of pain in his right knee after completing his first session.

Subsequent scans have revealed minor medial ligament damage, although Poom is still expected to be in contention for the trip to Cardiff on December 11.

"I just felt something in my knee when I was training and understandably I was concerned," said Poom.

"But it seems to be okay - I'll take some rest and it should be fine."

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