Despite a tense afternoon on Sunday lunchtime, Chelsea fought hard and eventually snatched a 1-0 win over a resolute West Brom side, who defended well collectively for sustained periods but were punished for a costly second half mistake.

Diego Costa netted his 12th Premier League goal of the campaign with a well-taken strike from close-range after Gareth McAuley dithered in possession. Upon reflection, it was unlikely that the Baggies would take anything from the game itself but started well, and showed they did their pre-match homework by doubling up on defensive duties to isolate the likes of Costa and Eden Hazard for large periods at Stamford Bridge.

Chelsea's Brazilian-born Spanish striker Diego Costa celebrates after scoring the opening goal of the English Premier League football match between Chelsea and West Bromwich Albion at Stamford Bridge in London on December 11, 2016. / AFP / Justin TALLIS / RESTRICTED TO EDITORIAL USE. No use with unauthorized audio, video, data, fixture lists, club/league logos or 'live' services. Online in-match use limited to 75 images, no video emulation. No use in betting, games or single club/league/player publications. / (Photo credit should read JUSTIN TALLIS/AFP/Getty Images)
Chelsea’s Brazilian-born Spanish striker Diego Costa celebrates after scoring the opening goal of the English Premier League football match between Chelsea and West Bromwich Albion at Stamford Bridge in London on December 11, 2016. (Photo: Justin Tallis / AFP / Getty Images)

The victory means Antonio Conte’s side are now three points clear at the top of the table with 37 points from 15 matches, having won nine successive league matches to date. This is in stark contrast to Chelsea’s struggles earlier in the season, where many critics were questioning Conte’s reasoning behind a formation change: with the acquisitions of David Luiz and Marcos Alonso as well as an emerging Victor Moses, the Blues have only conceded two league goals since their 3-0 defeat against Arsenal in late September.

LONDON, ENGLAND - DECEMBER 11: Cesar Azpilicueta and David Luiz of Chelsea celebrate their team's 1-0 win after the Premier League match between Chelsea and West Bromwich Albion at Stamford Bridge on December 11, 2016 in London, England. (Photo by Julian Finney/Getty Images)
LONDON, ENGLAND – DECEMBER 11: Cesar Azpilicueta and David Luiz of Chelsea celebrate their team’s 1-0 win after the Premier League match between Chelsea and West Bromwich Albion at Stamford Bridge on December 11, 2016 in London, England. (Photo by Julian Finney/Getty Images)

They face bottom side Sunderland away in midweek, and given their recent form, they’ll be expecting to travel back to west London with no less than all three points against David Moyes’ team. Their 3-0 defeat at the hands of Swansea on Saturday is their tenth league defeat of the season.