Chelsea 1 Middlesbrough 0: Chelsea leapfrogged Arsenal to reclaim second place and cut Manchester United's advantage at the Premier League summit to five points with a narrow victory over Middlesbrough.

A rare goal by defender Ricardo Carvalho ended up settling the contest but Boro left Stamford Bridge wondering how they had not come away with at least a point, a feat they had achieved at Arsenal a few weeks earlier.

Substitute Afonso Alves was the main culprit by hitting the woodwork twice with the goal at his mercy and defender David Wheater also headed against the crossbar.

Chelsea had to ride their luck to win a game they could have sewn up much earlier had they taken chances of their own and Avram Grant's side can now breathe a sigh of relief before turning their attentions to Wednesday night's Champions League showdown in Istanbul against Fenerbahce.

Carvalho goals do not arrive very often but usually they have worth. The defender had not found the net for almost a year following his only goal of the game against Tottenham in April 2007.

Wayne Bridge was the supplier this time, when he floated a sixth-minute free-kick into a crowded box.  Carvalho was beyond the penalty spot but nonetheless was able to place his header out of Schwarzer's reach to give his side the lead.

Boro looked shell-shocked and were relieved when Drogba's header flashed into the side-netting from a corner but the visitors eventually gained enough composure to respond.

George Boateng and Stewart Downing caused trouble with long-range efforts and home goalkeeper Carlo Cudicini was caught out by a Luke Young cross that needed the recalled Juliano Belletti to head behind.

But the clear-cut chances belonged to the title contenders and Joe Cole fired wastefully over after Drogba had set him up with a cushioned lay-off.

The half ended with Drogba unable to record his 14th goal of the season. First a free-kick was deflected just wide and then, after Cole had crossed from the right, the striker planted a free header over.

Chelsea dominate early in the second half but Mikel John Obi and Essien were both off-target with long-rangers.

Tuncay Sanli's afternoon, which had seen him come off worse in a first-half clash of heads, ended just after the hour mark when the heavily-bandaged Turk was replaced by Alves.

Chelsea then replaced Ballack with Shaun Wright-Phillips, who immediately wasted two excellent chances.

The first, after Cole had put him through, he rolled past Schwarzer but inches wide of the far post. The second was sent looping over the bar after Kalou had given him another sight of goal.

The winger was almost made to pay for his profligacy as Alves wasted his side's best chance, heading wide after Downing had picked him out in the box with a clever left-footed curler from the right.

Luck favoured Chelsea from the next attack when Cudicini came out to meet Cattermole's ball for Alves to chase — and failed to make contact.

Defenders poured back but Alves calmly took aim — and hit a post, with Cudicini gratefully grabbing the rebound.

Astonishingly, the substitute hit the goal-frame again — this time the bar — with Wheater doing exactly the same from the rebound and Chelsea were at last able to breathe easily when Jeremie Aliadiere failed to hit the target seconds later.

Boro threw men forward in added time — including Schwarzer — but Chelsea hung on for a victory that should have been far more comfortable.