Sunderland 2, Wolverhampton Wanderers 1.

THERE is a commonly-held perception that when Mick McCarthy exited the Stadium of Light last March, the only legacy he left behind was an ingrained stain of failure.

To chairman Niall Quinn, McCarthy's legacy was the "gremlin" that wrecked the opening stages of this season.

To manager Roy Keane, the Irishman's parting present was a squad of players that was incapable of returning Sunderland to the Premiership.

And to the club's supporters, scarred by the trauma of last season's record-breaking relegation, McCarthy's name will forever be associated with a deep disillusionment that has taken the best part of a year to lift.

Forget the memory of the Championship title, when it comes to assessing the Wolves manager's standing at the Stadium of Light, the tragedy greatly outweighs the triumph.

So when McCarthy made his maiden return to Wearside on Saturday, the occasion was supposed to provide evidence of just how radically the club has been transformed under the guidance of his long-term successor, Keane.

On paper, Sunderland's 2-1 victory, a success that extended their current unbeaten run to 15 games and took them within a point of league leaders Derby, did exactly that.

But beyond the headlines of a predictably fruitless return, McCarthy was able to extract a modicum of satisfaction from an afternoon that suggested that his parting gift to Sunderland was more substantial than a litany of let-downs.

After all, it was he who pilfered Daryl Murphy, scorer of the opening goal, from Irish club Waterford for the princely sum of £100,000.

It was he who signed Nyron Nosworthy, the game's most impressive defender, on a free transfer from Gillingham, and he who shelled out £140,000 to sign Danny Collins, a revelation at left-back in the second half of this season.

So while it wasn't quite revenge as McCarthy saw his Wolves side slip out of the play-off places, there was certainly an element of vindication in the identity of the home side's leading lights.

"It was nice to see one or two of the players that I signed still in starring roles," said McCarthy, who received a mixed reaction from the home fans. "Although I'm a bit annoyed that Murphy chose this game to score in.

"It's good to see some of the lads I know playing. Nyron's really performing at the back, and I was never really able to get him to do that there.

"I argued with him long and hard about it, but he never fancied playing at centre-half.

"Maybe Roy's got more ability to coerce somebody to play out of position for him. His persuasive qualities must be better than mine.

"I think they'll take some stopping - but I said that before this game.

"There's a lot of quality in their team and it looks like, if they go up, Roy might have a few quid to spend, unlike a certain old fella who has been here before."

Promotion remains anything but a formality, of course, but McCarthy was not the only Sunderland stalwart aiding his former club's cause at the weekend.

While three of the Irishman's signings played starring roles at the Stadium of Light, another - Steve Caldwell - helped a Steve Cotterill-led Burnley side to a surprise 1-0 win at Birmingham that could yet prove pivotal in the race for the Premiership.

The result does not mean that Sunderland's fate is in their own hands - Birmingham are now two points behind the Black Cats with a game in hand - but it does mean that the momentum at the top of the Championship table has swung decisively in their favour.

"Other results don't interest me one little bit," argued Keane on Saturday night, with a mischievous grin that suggested he is already mastering the mind games so beloved of his former boss, Sir Alex Ferguson. "Until tomorrow at least.

"The important thing is that we carry on doing what we're doing. Winning - that's what we're in the game for.

"The players have taken on board what I'm trying to do, and that's trying to get a winning football team. We don't want to be doing things half-measured.

"This was another test against a big strong team. It was a tough match, but the players dug deep and came through it."

Not only that, but they also underlined that they are going to try to win promotion by sticking to their principles.

Faced by an aggressive Wolves side led by midfield man mountain, Seyi Olofinjana, it would have been easy for Sunderland's more creative players to have retreated into their shells.

Instead, in front of the club's biggest crowd of the season, the fit-again Carlos Edwards and the impressive Ross Wallace performed impishly on the flanks, Liam Miller flitted here, there and everywhere in central midfield, and Murphy displayed a mature awareness to play off the powerful Stern John.

There might have been no David Connolly, Anthony Stokes or Tobias Hysen - rested ahead of this evening's trip to Southampton - but the strength of Sunderland's squad was clear to see. With the games continuing to come thick and fast, it could make all the difference in the final month of the season.

"We were caught short when I first got the job," admitted Keane. "But since New Year we've had a much more settled squad and you can't beat competition for places. The players know they need to be at it each and every day."

Murphy was certainly at it in the early stages of Saturday's game, with the Irishman firing the Black Cats into a 15th-minute lead courtesy of a virtuoso display of skill.

Tangling with former teammate Neill Collins in an attempt to reach Wallace's cross, the 24-year-old controlled a looping loose ball on his chest before drilling an instinctive first-time volley into the bottom right-hand corner.

A fantastic last-ditch challenge from Nosworthy denied Andy Keogh as Wolves sprang Sunderland's offside trap on the half-hour mark, and the hosts were unfortunate not to double their lead in first-half stoppage time.

Dean Whitehead's pull-back found John, but the Trinidad & Tobago striker, no doubt buoyed by the presence of a 200-strong group of fans from his homeland, dragged his shot against the inside of the left-hand post and into the grateful arms of Matt Murray.

Darren Ward kept Sunderland's lead intact with a fantastic second-half save to tip Olofinjana's looping header over the crossbar, and the points looked to be safe when Wallace, who scored the winner at Cardiff last weekend, peeled away at the back post to head home Murphy's right-wing cross.

"He's had a good week, put it that way," said Keane. "I'm sure he'll enjoy his Easter eggs now."

The celebrations were temporarily put on hold when Keogh stole in to convert Michael McIndoe's left-wing cross two minutes later, but while Wolves substitute goalkeeper Jan Budtz produced three smart saves late on, Sunderland's lead was rarely troubled.