Arsenal closed the gap on Premier League leaders Liverpool to 12 points by winning their game in hand on Sunday.
Mikel Merino headed home from a Martin Odegaard corner in the first half as Arsenal extended their unbeaten run against Chelsea to seven games.
Both Arsenal and Liverpool now have nine league fixtures remaining this season, including their clash against each other at Anfield on May 10.
While Arsenal's title hopes remain very slim, Sunday's victory strengthened their hold on second place, with Mikel Arteta's men now four points clear of Nottingham Forest in third.