Eden Hazard scored a goal in each half to take his Chelsea tally to 101 and earn a battling win.
The Belgian had raced clear to put the Blues ahead with a sumptuous opener in first-half injury time, only for Roberto Pererya’s stunning volley to draw Watford level seconds before the break.
But with the home side stepping up the tempo and playing a direct style that had Chelsea increasingly rattled, Hazard won and converted a penalty to restore the lead and victory was closed out with little concern in the closing stages.
Maurizio Sarri’s side, who move two points ahead of Arsenal in fourth, controlled play in the final half an hour and should have added to their lead, with N’Golo Kante and Willian both missing excellent chances.
Chelsea had been on top in the first half, with Pedro curling an early effort wide and Willian hitting the post after a swift counter-attack.
Hazard then missed a glorious chance, completely mis-kicking from Cesar Azpilicueta’s teasing right-wing cross.
Watford looked a threat on the break and Troy Deeney and Abdoulaye Doucoure both had strikes blocked, while Kepa Arrizabalaga made a fine point-blank save.
Willian and Pedro were both finding plenty of space but Pedro’s match finished early with what looked like a hamstring injury and he was replaced by teenager Callum Hudson-Odoi.
Chelsea led when Hazard, once again playing as a striker, raced onto Mateo Kovacic’s pass after Watford lost possession in midfield and shifted the ball past keeper Ben Foster at speed before sliding in his 100th Chelsea goal.
But moments later Pererya crashed in a brilliant first-time volley after Chelsea lost concentration at a corner.
But Hazard’s second-half goal put Chelsea back on track, the game’s outstanding player settling the nerves from the spot after racing onto Jorginho’s cute ball over the top and being bundled over by Foster.
Kante should have wrapped up the points after a glorious give and go with Hazard, but the Frenchman shot just wide of the far post.
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This post was last modified on 26/12/2018