By Joe Nelson

Arsenal enjoyed one of their finest performances in recent years on Saturday evening in a 3-0 drubbing of Chelsea.

This victory against their fierce London rivals announced their intentions as a clear title challenger this season.

First-half goals from Alexis Sanchez, Theo Walcott and Mesut Ozil were enough to see off the visitors, with the second half being a straight-forward affair with the match beyond Chelsea’s reach.

Here are three things we learned from the Gunners’ impressive victory:

Iwobi will not be dislodged easily.

Alex Iwobi may not have registered any goals or assists during the match, but was named as the Premier League’s ‘Man of the Match’ after a fine display.

His awareness to pick out pockets of space and exploit them ruthlessly played a big part in the lead up to the Gunners’ second goal, which was finished off by Theo Walcott after the ball being laid on a plate for him by Hector Bellerin.

The 20-year-old also created a golden opportunity for Walcott in the second half, in which he struck the legs of Thibaus Courtois.

Many Arsenal fans believe Alexis Sanchez should occupy the left-hand-side role with the returning Olivier Giroud moving up-front. But while Iwobi continues to sparkle from the wing, expect no changes in the imminent future.

Mustafi the man to partner Koscielny

The in-form Diego Costa was brilliantly handled by the defensive duo of Laurent Koscielny and Shkodran Mustafi on Saturday night, with the Spanish striker registering his first shot on-target in the 82nd minute.

The German arrival had looked shaky in his opening games for the Gunners, but was outstanding at the back on Saturday, as the pair closed up shop and neutralised Chelsea’s attacking threat almost seamlessly.

Petr Cech only save-of-note of the game came when Michy Batshuayi broke through their back-line in the closing minutes, only to be denied by Cech’s legs.

Walcott is back to his best

The man-of-the-match award could have been handed to almost anyone wearing an Arsenal shirt yesterday. But there were none more deserving than Theo Walcott.

The winger put in an exemplary shift on the fight-hand side, as he not only scored the second goal, but helped track back on numerous occasions to deal with the threat of Eden Hazard.

When questioned about the Englishman’s attitude after the game, Wenger replied: “I think you cannot question his performance,” as quoted by the Evening Standard.

“I believe more the change of Theo Walcott is his attitude this season.”

In other Arsenal news, Didier Drogba sent a scathing message to Walcott following the win.