Two second half goals from Gabriel Martinelli and substitute Emile Smith-Rowe was all Arsenal needed to earn a 2-0 derby victory over Westham.
Arteta’s side came into the encounter after a 3-0 outstanding victory at home against Southampton while David Moyes’ side travelled to Emirates following a 0-0 draw at Turf Moor last weekend.
Both sides ended the first half goalless as the Gunners missed a flurry of chances.
Arteta’s men finally broke the deadlock through Martinelli who sprinted through an opening in the Hammers’ defence before calmly slotting the ball past Fabianksi.
Westham were reduced to 10 men when Vladimir Coufal was sent off having received two yellow cards for a foul on Lacazette during the game. The Frenchman stepped up but saw his effort saved by Lukasz Fabianksi.
The North-London outfit ensured their victory three minutes from regular time through Emile Smith-Rowe who came off the bench to get their second goal of the game.
The win sends Arsenal into the top 4 for the first time this season.