The claim from chief executive Peter Kenyon that Chelsea manager Avram Grant has the absolute confidence of the Stamford Bridge hierarchy will no doubt be reviewed at the end of the season. But for now, Grant appears to be doing just enough as his side ground out an unconvincing win to sustain their challenge for the title.

Chelsea’s hopes of regaining the championship, and therefore offering Grant the chance of job security, are likely to lie with their results in home games against Arsenal and Manchester United in the closing weeks of the season, but it is debatable whether they will face a much sterner examination than provided here.

Maximum points from the post-Barnsley FA Cup debacle against Derby and Sunderland were a minimum requirement and John Terry’s early goal yesterday ensured that was the case. But whereas Derby had simply laid down and died in midweek, the Black Cats bared their claws and made Chelsea fight all the way.

The visitors did at least prove they have that invaluable quality in their armoury and Roy Keane must also know that his side is up for their particular battle. No goals and no wins in five games are a concern but Sunderland did create chances and had Chelsea hanging on at the end. Similar performances against Fulham, Newcastle, Middlesbrough and Bolton during their run-in should bring them the rewards needed to stay up.

It took Chelsea just 10 minutes to take the lead, which would have been damaging enough at the best at times but, for a goalshy Sunderland side going behind, even so early in the game, looked likely to be catastrophic.

Keane had brought back Carlos Edwards and Roy O’Donovan to try and increase Sunderland’s potency and Kenwyne Jones did trouble both Terry and Alex with his aerial power.

One flick-on from Jones allowed O’Donovan to get goal-side of Terry but even though the Irishman went to ground under the Chelsea captain’s challenge, even Keane would have been hard pressed to claim a penalty.

Terry was soon making his muscular presence felt at the other end when he headed home his first goal of the season. Sunderland had already been reliant on a superb tackle from Jonny Evans to halt Salomon Kalou’s run on goal and a Danny Collins block from Joe Cole’s follow-up to keep Chelsea at bay but when the England midfielder delivered a corner from the left, Terry gave Jones the slip to head in at the near post.

Chelsea appeared set for a comfortable afternoon and having put six past Derby days earlier might have envisaged further shooting practice as the fluidity of their attack, led by Didier Drogba rather than Nicolas Anelka, had Sunderland fully stretched.

Yet despite a record of six defeats in six matches against the top four this season, Sunderland’s inferiority complex did not last long as they refused to be cowed. Andy Reid led the riposte, with Jones and O’Donovan continuing to cause a nuisance, particularly to Carlo Cudicini whose overreaction to a slight, if out of order, touch from O’Donovan confirmed the impression that Chelsea did not enjoy not having it all their own way. Cudicini did, though, deserve credit for a fine save to deny Reid, who makes up for a lack of athleticism with a wonderful left foot that would have brought Sunderland level by the break but for the Chelsea goalkeeper, who diverted his free kick away from the top corner.

Unfortunately for Sunderland, Reid’s right foot is not so cultured, as he showed in fluffing a chance early in the second half, although when his miscue found its way to Grant Leadbitter the midfielder had Cudicini scrambling to concede a corner that Collins headed not too far wide.

Chelsea needed the cushion of the second goal that Frank Lampard nearly gave them in first-half stoppage time when Craig Gordon was forced to make a rare save but Sunderland allowed Lampard, Michael Ballack and Joe Cole so little time on the ball that the paucity of chances created made Drogba a virtual spectator.

Grant’s concern was reflected in his replacement of Ballack with Michael Essien as the visitors looked to protect their lead, while at the same time Keane sent on Dwight Yorke as a replacement for O’Donovan.

Within moments of his arrival, Yorke provided the chance for Jones that should have seen Sunderland equalise with 15 minutes to go. Drifting into the penalty area, Jones was superbly picked out by Yorke but the striker could only head weakly at Cudicini from 10 yards.

Jones had the opportunity to make amends in the 90th minute, again from a Yorke cross, but despite outjumping Terry the chance was more difficult and his header flew over the bar. Still Chelsea were not quite over the line, though, as with virtually the last kick of the match Dean Whitehead volleyed wide by inches, a margin that could yet have an effect at both ends of the table.

Star man: Dean Whitehead (Sunderland)

Player ratings: Sunderland: Gordon 6, Bardsley 6, Evans 7, Nosworthy 7, Collins 6, Edwards 5 (Prica 62min), Whitehead 8, Leadbitter 7 (Harte 85min), Reid 7, O’Donovan 6 (Yorke 73min), Jones 7
Chelsea: Cudicini 7, Ferreira 6, Alex 6, Terry 6, A Cole 6, Mikel 6, J Cole 7 (Wright-Phillips 82min), Ballack 5 (Essien 73min), Lampard 7, Kalou 6, Drogba 6

Yellow cards: Sunderland: Leadbitter Chelsea: Mikel

Referee: M Dean

Attendance: 44,679