MICK McCarthy has refused to discuss Marcus Stewart's contract situation until the end of the season, because the Black Cats boss thinks the uncertainty is helping to focus the striker's mind.

Stewart grabbed his second hat-trick in the space of five months in Saturday's convincing 4-2 win over Watford, taking his tally to 12 goals for a season widely predicted to be his last at the Stadium of Light.

After being signed by Peter Reid in August 2002, Stewart is one of the last remaining links to Sunderland's Premiership past and, consequently, his current deal reflects the club's more lavish days. That almost led to him leaving Wearside in the summer but, after a prospective move to Bristol City failed to materialise, the 32-year-old found himself back in McCarthy's starting line-up at the start of the current campaign.

He has endured his ups and downs since then, but Saturday's match-winning display proved just how valuable a commodity he remains.

Some tough decisions will have to be made in May and, while much will depend on where Sunderland are playing their football come the start of next season, McCarthy is happy to have a sense of uncertainty keeping his most experienced striker on his toes.

"We will discuss his situation at the end of the season," said McCarthy, who is unlikely to embark on the same wholesale squad overhaul he oversaw last summer.

"The nice thing about players whose contracts are almost up is that they seem to play with a spark about them.

"You find people work hard and look lively. Marcus is not insecure about his situation, so I don't think there's any reason to discuss it now. Let's see where we end up at the end of the season."

McCarthy always insisted that Stewart's possible departure was due to financial, not footballing concerns, and, with the Black Cats hanging onto the coat-tails of the Championship top two, the 'For Sale' sign has been taken from around his neck.

"Marcus was available for transfer due to financial issues at the club at the start of the season," he said. "Quite clearly he is not going anywhere at the moment though.

"Over the last six or eight weeks, Marcus has been superb but I think the only difference between now and a few months ago is that he is putting the ball in the back of the net.

"Before, when I was saying that Marcus and Stephen Elliott was the best partnership at the club, Elliott was getting the goals and Stewart was much maligned at times.

"So it was lovely to be able to take him off after an hour (against Watford) and see him get the standing ovation he deserved."

With Sunderland's recent injury problems having subsided, McCarthy was able to name an unchanged side for the visit of Watford.

The club's Christmas blip came when the likes of Carl Robinson and Jeff Whitley were nursing bumps and bruises, and the former Republic of Ireland boss insists it is no co-incidence that his side have recovered their consistency when changes have been kept to a minimum.

"Keeping the side the same helps," admitted McCarthy. "I think it helps when players know that they're going to play. They know that, in my mind at least, that's what I think my best team is. It gives players a bit of confidence, and it's great for us as staff as well because we're not having to constantly drill things into different people.

"The players know their jobs, they know where they're meant to be when we're defending free-kicks or corners and that builds up an understanding."

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