Substitute Carlton Cole fired Sunderland to the brink of relegation as Chelsea kept their Champions League charge on full throttle.

However, Claudio Ranieri's side were made to fight all the way for the three points as the Black Cats turned in their best performance for months but still could not avoid a club record-equalling ninth successive league defeat.

Bolton's win over Manchester City earlier in the day means Mick McCarthy's men could effectively be only one game from relegation, and while that has been seemingly inevitable for some time, their performance this afternoon was worthy of more.

Indeed, the home supporters among a crowd of 40,011, who have delivered more than their fair share of boos in recent weeks, gave their side a standing ovation on the final whistle despite the knowledge that their fate is all but sealed.

Sunderland made life desperately difficult for the visitors throughout, Sean Thornton firing them into a 12th-minute lead which was eventually cancelled out seven minutes after the break by Gianfranco Zola.

But Cole's late intervention proved decisive and the writing is now on the wall for the Wearsiders.

Sunderland fans have not had a lot to cheer in recent months, and the fact that the only home win at the Stadium of Light in recent times was England's 2-0 victory over Turkey on Wednesday evening will have come as little consolation to the red and white faithful.

They arrived once again fearing the worst as high-flying Chelsea headed for Wearside knowing that another victory would strengthen their case for Champions League football next season and leave their hosts teetering on the brink.

But what unfolded could hardly have departed any further from the script as the leading candidates for relegation upstaged their illustrious opponents to take the game by the scruff of the neck before the break.

McCarthy has promised that if his side are to go down, they will go down fighting, and that philosophy had clearly had an effect as his players produced their best performance for months in the opening 45 minutes.

The manager went for broke by throwing Marcus Stewart and Kevin Kyle up alongside Kevin Phillips in attack, and the ploy worked as the Blues found life increasingly uncomfortable.

Kyle, so often the target of the critics in the stand, proved a real handful, while Phillips looked as sharp as ever.

But it was Stewart who helped to fashion the early breakthrough on 12 minutes when he got to the by-line and sent in a cross which was deflected by Mario Melchiot.

The ball dropped for Frank Lampard, but he could only head it as far as Thornton, who controlled with his chest before smashing an unstoppable volley past Carlo Cudicini.

It should have been 2-0 five minutes later when Kyle's wayward header from a Thornton corner fell for Stewart at the back post, but he sent the ball agonisingly wide as he slid in at full stretch.

Chelsea had their moments, but two superb interceptions by Talal El Karkouri denied Jimmy Floyd Hasselbaink and then Melchiot, while Thomas Sorensen saved from Zola after the Italian had deftly controlled Graeme Le Saux's long ball.

But the visitors emerged in more determined mood after the break and signalled their intentions from the off as Zola tested Sorensen with a curling right-foot effort and then Cole, on at the break for Enrique de Lucas, shot over from close range.

Cudicini kept out Gavin McCann's long-range effort as the home side rallied, but Ranieri's side were back on terms just seven minutes into the half when, after Cole had headed down William Gallas' cross, Zola's shot was deflected past Sorensen by the unfortunate El Karkouri.

It could have been even worse for the Black Cats seconds later after Hasselbaink raced clear and rounded the Dane before slotting home, but referee Dermot Gallagher ruled that he had handled the ball on his way to goal and chalked the effort off.

The game became increasingly tense as both sides struggled to create chances, but it was Sunderland who set the ball rolling once again on 71 minutes.

John Terry's foul on Kevin Kilbane handed the home side a free-kick in a dangerous position, but in his eagerness to catch the Blues' defence cold with a quickly-taken cross, Stewart only succeeded in serving up an easy ball for Cudicini.

However, the Italian was stretched two minutes later when McCann tested him with a perfectly-struck volley which he had to beat away as it dipped under the crossbar.

But just as it looked as though McCarthy's men would get something out of the game, Cole turned smartly on Hasselbaink's shot pass before blasting a left-foot shot past Sorensen.

Thornton came within inches of an equaliser with three minutes remaining when his free-kick clipped the outside of the post and ran to safety on an afternoon when the margin between success and failure proved agonisingly small.

Teams

Sunderland: Sorensen, Gray, El Karkouri, Bjorklund, Williams, McCann, Thornton, Kilbane (McCartney 86), Phillips, Kyle, Stewart.

Subs Not Used: Poom, Babb, Proctor, Arca.

Booked: El Karkouri.

Goals: Thornton 12.

Chelsea: Cudicini, Gallas, Desailly, Terry, Melchiot, Morris, Lampard, De Lucas (Cole 45), Le Saux, Zola (Zenden 88), Hasselbaink (Oliveira 90).

Subs Not Used: de Goey, Huth.

Booked: Cole.

Goals: Zola 52, Cole 85.

Att: 40,011

Ref: D Gallagher (Oxfordshire).