Diego Costa sent the Blues top of the Premier League with the only goal against plucky Middlesborough 1-0 at the Riverside Stadium this evening.
The Blues leapfrog Liverpool and have a two-point lead going into next weekend's derby clash with Tottenham Hotspurs.
This was not a vintage Chelsea performance but it was win - their six in a row with not a goal conceded in that time.
Chelsea starting 11 have remained unchanged for the past five games as the Blues inch their way towards the top of the Premier league.
While they look to be a goal-scoring threat whenever they attack, they do still look shaky at the back - something Middlesborough attempted to exploit in the early part of the match.
The Blues should have gone 1-0 up on 18 minutes, when Victor Moses, on the right, given the ball by Eden Hazard, cut inside but his left-footer, was wayward and well wide of Victor Valdes' goal.
In general, Chelsea were ponderous in attack, with Diego Costa the main culprit.
Pedro, had a gilt-edged opportunity on 28 minutes, when again, set up by Hazard, he contrived to blast the ball over the Boro crossbar, instead of taking an extra half second to control it and place it into the net.
But Chelsea's dominance finally bore fruit, four minutes from half-time, when a corner by Hazard looped up into the air off Calum Chambers. The home side players were guilty of ball-watching while Costa was quickest to react and slotted home a smart close-range left-footed volley past Valdez.
Chelsea almost doubled their lead seconds into the second half when Marco Alonso smashed a low drive straight at Valdes. The Spain goalkeeper could not hold the ball but Chambers was on the spot to clear it from danger.
gaston Ramirez had the home side's best chance on 56 minutes when Alvaro Negrado dummied the ball. It fell invitingly to Ramirez, but he arrowed his edge of the penalty area shot high over Thibaut Courtois's crossbar.
A sensational break by Chelsea on 64 minutes saw David Luiz rampage forward. He sent in a perfect cross which Costa headed into the path of in-running Pedro.
The Spain mdnfielder smashed the almost perfect left-footer towards goal from the edge of the Boro area. Valdes was beaten but the ball bounced off the apex of post and crossbar and was cleared.
A brilliant break by the home side on 78 minutes saw Courtois forced in to a fine diving save from a Adam Clayton half-volley as Chelsea were caught in the hop trying for the second goal.
Antonio made his fist substitution with 10 minutes on the clock, replacing a tired pedro for Nathaniel Chalobah.
Teams: Chelsea, Courtois, Alonso, Kante, Hazard, pedro, Moses, Costa, Matic, Cahill, Azpilicueta, Luiz
Subs, Begovic, Ivanovic, Fabregas, Oscar, Batshuayi, Terry, Chalobah
Middlesborough, Valdez, Gibson,, Negredo, Clayton, De Roon, Barragan, Ramirez, Chambers, Forshaw, Traore
Subs, Guzan, Bernardo, leadbitter, Rhodes, Fischer, Downing, Nsue
Chelsea's dominance of the opening 45 minutes at the Riverdide Stadium against Middlesborough saw the Londoners take the lead four minutes before the break.
Diego Costa was the quickest to reacxt after the ball looped into the air from a corner.
While the home side ball-watched, Costa reacted quickest and flashed a close-range left-footer volley past Victor Valdez.