English Premier football League

Chelsea on top

 It was the London side's sixth successive league victory without conceding a goal and put them on 28 points from 12 games, a point ahead of the Merseyside club and Manchester City.

The league's leading scorer, Costa, hit his 10th goal of the season to put them in front four minutes before the break.

'Boro, promoted last season, found it hard to make any clear opportunities against a solid Chelsea defence and remain in the bottom six, one point clear of the relegation places.