Pedro scored a brace and Eden Hazard netted a world class goal to help the Blues retain their top position with a convincing 5 points lead above second-placed Manchester City.
The Cityzens move up the table to second overtaking Liverpool as they beat Hull City 3-0. Yaya Toure, Kelechi Iheanacho scored a goal each and a Curtis own goal sealed the fate of the match in favour of Manchester City.
Arsenal fought hard to pick up crucial three points against a tough West Brom side at the Emirates Stadium. Olivier Giroud's late header ensured the Gunners the much-needed win.
Manchester United collected their third consecutive win as they convincingly beat Sunderland 3-1 at the Old Trafford. David Moyes who had previously served as Man United manager returned to Old Trafford after 2.5 years and it turned out to be an embarrassment for him.
Zlatan Ibrahimovic, Daley Blind and Henrikh Mkhitaryan scored for the Red Devils.
Here are the results from Day 1 of game week 18
Watford 1-1 Crystal Palace
Arsenal 1-0 West Brom
Burnley 1-0 Middlesbrough
Swansea 1-4 West Ham United
Manchester United 3-1 Sunderland
Chelsea 3-0 Bournemouth
Leicester City 0-2 Everton
Hull City 0-3 Manchester City
Tuesday, Dec 27
Liverpool 4-1 Stoke City
Wednesday, Dec 28
Southampton 1-4 Tottenham Hotspur