Blues stay five points clear
Under siege Chelsea retained a five-point lead at the top of the Premier League after repelling Manchester City at Stamford Bridge.
Loic Remy, deputising for the suspended Diego Costa, struck four minutes before the break, but David Silva deflected in Sergio Aguero's shot to restore parity.
It was no less than City deserved, having had the better of the opening 45 minutes, but the holders could not find a breakthrough in the second period in a 1-1 draw.
The visiting supporters sang "champions of England, we know what we are" throughout, much to the bemusement of Jose Mourinho, who knew a point would consolidate his side's advantage and be of little assistance to City's bid to retain the title.
So fuming was Mourinho with Costa's three-match ban for stamping on Liverpool's Emre Can - something which likely only heightened his view of a "clear campaign" against Chelsea - that he stayed silent on the eve of the match.
But, dressed down in his club tracksuit, he stood on the edge of his technical area throughout and questioned every decision which had a hint of being contentious.
City tried to suffocate Chelsea, hoping to expose the fatigue of the additional 30 minutes against Liverpool and the hosts were hemmed into their half for much of the second period.
Frank Lampard, Chelsea's record goalscorer, came on for City with 14 minutes remaining to applause and the odd dissenting voice.
Lampard scored the equaliser in the September clash between the sides, but was unable to do so on this occasion to leave his former side in pole position for the title with 15 games remaining.
Still City, who halted a run of two straight losses, have not won a Premier League game in the absence of Yaya Toure this season and they are playing catch up in the title fight.
Chelsea's challenge, meanwhile, is to be boosted by the imminent arrival of Fiorentina's Juan Cuadrado, who was in attendance at Stamford Bridge.
Chelsea's hopes of extending their advantage over City were hit by injuries to Cesc Fabregas (hamstring) and Filipe Luis (calf), who joined Costa in missing the contest.
Cesar Azpilicueta, Ramires and Loic Remy came in, with the fresher legs needed after Tuesday's energy-sapping defeat of Liverpool.
City, with a side showing five changes following the FA Cup loss to Middlesbrough, began well.
Jesus Navas stung the palms of Thibaut Courtois in the opening minute and Branislav Ivanovic then gave the ball away and was relieved to see Fernandinho fire wide across goal.
Kurt Zouma, continuing in defence ahead of Gary Cahill, halted Sergio Aguero, who then had an effort saved by Courtois.
Vincent Kompany then lost out to Remy as Chelsea broke down City's left.
The France striker pulled the ball back towards Hazard, who left it for Oscar. The Brazilian could only shoot straight at Joe Hart.
Aguero should have put City in front but only after Ramires had looped the ball on to Martin Demichelis' hand.
It would have been a harsh handball and referee Mark Clattenburg waved play on. City broke, but Aguero dragged his shot wide.
The miss proved costly when Chelsea struck as Willian, full of running in the opening half, shoved Gael Clichy off the ball.
Ivanovic clipped the ball over the top for Hazard to cross with a volley which Kompany missed - Remy did not though as he netted from close range.
First blood to Chelsea, but City's response was almost immediate.
Courtois missed Navas' whipped cross and Aguero picked up the ball and shot. Ivanovic was on the line, but Silva slid in to redirect the ball and convert.
City resumed with purpose and Navas beat Azpilicueta down the left to cross for Fernandinho, whose header into the ground forced Courtois to tip over.
Mourinho felt Chelsea should have had a free-kick for a Fernando challenge on Ramires and was outraged to see Nemanja Matic penalised for a challenge on Silva.
His team were absorbing the pressure well, but the Blues boss knew one mistake could prove costly.
Advances into enemy territory were all too fleeting for Chelsea, who soon had their record goalscorer and servant of 13 years in opposition.
The 36-year-old Lampard, who had said he would never play for another Premier League club and will join New York City FC at the end of the season, was met with a few boos, but the majority of the home support raised their voices for Chelsea.
It was like an attack versus defence training drill as the match entered its final 10 minutes, with Mourinho unhappy with Remy for losing the ball in City's half.
Cahill replaced the striker with three minutes to go, providing a defensive reinforcement, but City were struggling to break down the rearguard.
James Milner shot wide across goal and the visitors had to be satisfied with a point which ended Chelsea's 100 per cent home record in the Premier League this term.