Arsenal beat London rivals Chelsea 1-0 on Sunday for their first win in four Premier League games, with a header from substitute striker Mikel Merino boosting their slim hopes of catching leaders Liverpool.

Merino opened the scoring in the 20th minute when he stooped to head Martin Ødegaard's corner over Robert Sánchez in the Chelsea goal.

The midfielder, who has led Arsenal's attack in recent weeks in the absence of injured colleagues, came close to adding a second in the 60th minute, but his side-footed volley was well saved by Sanchez.

Chelsea were also short of firepower up front, with top scorer Cole Palmer missing and centre-forward Nicolas Jackson also out with injury.

Without them, Chelsea struggled to threaten the Arsenal backline. The closest they came to an equaliser was in the 37th minute, when defender Marc Cucurella's angled volley at David Raya went through the Arsenal goalkeeper's hands and just wide.

The win left second-placed Arsenal 12 points behind Liverpool, who were beaten by Newcastle United in the League Cup final on Sunday.

The top two teams have played 29 games each, with nine rounds of fixtures remaining.

Chelsea are fourth, one point ahead of Manchester City and five behind third-placed Nottingham Forest.