Chelsea have returned to winning ways in the Premier League with a 2-1 victory over Watford.

Roberto Pereyra cancelled out Eden Hazard's opener in the Boxing Day clash at Vicarage Road, but Hazard followed up netting his 100th goal in a Chelsea shirt by scoring from the penalty spot after half time to give the Blues all three points.

Maurizio Sarri's side remain in fourth position in the standings and now sit two points above fifth-placed Arsenal, while Watford are ninth after suffering their first defeat in four games.

Chelsea started on the front foot with Pedro curling a 20-yard effort marginally wide of the post, before Willian struck the woodwork from an acute angle after rounding goalkeeper Ben Foster.

There was a lengthy break in play while Christian Kabasele received treatment for a game-ending injury after sliding into the post, and the stoppage resulted in Chelsea losing their early rhythm.

Watford had the better of the play as the first half progressed past the half-hour mark, and Ken Sema should have done much better from 16 yards out but could only fire harmlessly over the crossbar.

Chelsea improved before the break but Hazard failed to convert from four yards out after being found by a low Cesar Azpilicueta cross, and Chelsea were dealt a further blow when Pedro needed to be replaced after sustaining what appeared to a hamstring injury.

However, the Blues went ahead in the first minute of added-on time as Mateo Kovacic played the ball through to Hazard, who was able to round Foster and fire into an empty net for his 100th goal since arriving at Stamford Bridge in 2012.

Sarri would have expected his team to see out the remainder of the first half, but Watford found an instant leveller when Pereyra was picked out on the edge of the area with the Argentine proceeding to send a 20-yard volley into the bottom corner.

Both teams went on the offensive after the restart without creating a clear-cut chance, but Chelsea were soon back in front from the penalty spot.

Hazard latched onto a through-ball by Jorginho before being clattered by Foster, and the Belgian got back to his feet to send the goalkeeper the wrong way from 12 yards.

That goal knocked the energy out of Watford and Chelsea went in search of a third and game-clinching goal, and it almost arrived through Willian who sent a fizzing half-volley marginally wide of the far post.

N'Golo Kante also fired a shot just off target after being sent through by Hazard, but Watford went straight down the other end and Troy Deeney flicked over the bar from close range after beating David Luiz at the front post.

Watford began to find gaps in the Chelsea defence and it led to Sarri replacing Callum Hudson-Odoi - who had been introduced for Pedro in the first half - with defender Emerson Palmieri, but Chelsea continued to create opportunities going forward.

Jorginho and Willian were both unfortunate not to find the back of the net and Foster made a fine save from Hazard after previously attempting a 20-yard overhead kick at the other end as Watford looked for a dramatic equaliser, but Chelsea were able to register another welcome three points on the road.

WATFORD (4-4-2): Foster; Femenia, Cathcart, Kabasele (Mariappa 16'), Holebas; Sema (Quina 67'), Doucoure, Capoue, Pereyra; Deulofeu (Success 82'), Deeney

CHELSEA (4-3-3): Arrizabalga; Azpilicueta, Rudiger, Luiz, Alonso; Kante, Jorginho, Kovacic (Barkley 80'); Pedro (Hudson-Odoi 43', Palmieri 85'), Willian, Hazard