Chelsea recorded a sixth straight home win as an improved second-half display proved too much for Brighton at Stamford Bridge.
Antonio Conte’s side were frustrated in an opening period in which Tiemoue Bakayoko and Victor Moses missed chances from close range.
But less than a minute into the second half Alvaro Morata headed his 10th Premier League goal from Cesar Azpilicueta’s fine cross.
The goal changed the dynamic and eased pressure on the home side, while Brighton never looked capable of mounting a serious threat.
And after forcing two saves in one minute – first from a free-kick and then from a header – Marcos Alonso sealed the win moments later with a glancing header from Cesc Fabregas’ corner.
The win moves Chelsea to one point behind second-placed Manchester United but they remain 13 adrift of Premier League leaders Manchester City, who play Newcastle on Wednesday.
Comfortable Chelsea in hectic period
Chelsea are unbeaten at the Bridge since defeat by Manchester City on 30 September.
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They continue to give chase with this win, which offered grit in contrast to the free-flowing football which Pep Guardiola’s side have served up this season.
There was nothing scintillating to be seen from the defending champions but Hazard consistently looked likely to unpick a stubborn 4-5-1 set-up by Chris Hughton’s side, as did Fabregas who along with Azpilicueta, played 108 passes.
Conte’s side fired 25 shots at goal in all but it was in the second period where they visibly showed more intent from the off and Morata – banned for the draw at Everton on Saturday – ran between defenders to head powerfully into the net.
The 25-year-old, a £60m summer signing, grew in confidence and Chelsea’s play showcased increasing freedom as Hazard flashed a shot wide from the next attack.
Alonso deserved his goal for three good efforts in a matter of minutes, and both he and fellow wing-back Moses played high up the pitch against a side showing minimal ambition.
Conte – who tellingly pushed Bakayoko further forward to exert more pressure at the break – will be thrilled with the simplicity of this win at a time when his side face three league fixtures in nine days.
The Blues are seven points worse off than after 20 league games last season but Conte can take comfort from nine wins in 12 league games.
Chelsea are showing admirable consistency but City’s brilliance looks set to render it meaningless.
