London, March 16 : Mikel Merino's first-half header proved to be the difference as Arsenal secured a hard-fought victory over Chelsea in a fiery London derby at the Emirates Stadium on Sunday.

The Spaniard, starting his sixth consecutive game up front, flicked in Martin Odegaard's corner in the 20th minute to give Arsenal the lead. It was a deserved advantage after a dominant opening period, where the Gunners piled on the pressure with multiple attempts.

From the outset, Arsenal looked dangerous. In the first 20 minutes alone, they registered six attempts. Jurrien Timber came close with a header while Leandro Trossard and Gabriel Martinelli also tested Chelsea's defense. A potential handball from Marc Cucurella was waved away and Declan Rice and Trossard both came close to scoring. The goal eventually arrived when Martinelli won a corner, and Odegaard's delivery was met by Merino, who flicked it past Robert Sanchez.

Chelsea struggled to break through, and although they had some moments of pressure, Arsenal held firm. Their best chance came just before halftime when Cucurella's shot squirmed through David Raya's grasp but narrowly missed the post. In the second half, Merino nearly doubled Arsenal's lead with a powerful volley that Sanchez did well to keep out.

As the match wore on, Chelsea attempted to build pressure but couldn't break Arsenal's defense down. Despite a few nervy moments and a couple of late fouls, the Gunners maintained control and sealed the victory. The result not only kept them firmly in second place but also extended their unbeaten run against Chelsea to seven Premier League games.

In a game full of intensity, Merino's solitary goal proved enough as Arsenal held on for the three points.

/IANS