Robin van Persie scored one goal and made two more as Arsenal secured a fourth consecutive Premier League win by cruising past West Bromwich Albion.
Arsenal led 2-0 at the break through Van Persie's tap-in and a Thomas Vermaelen shot from Van Persie's pass, despite not being at their fluent best.
But the Gunners dominated the second period against a West Brom side who only managed one effort on target.
And Mikel Arteta's fine strike sealed the victory after a sweeping move.
Arteta's classy 15-yard effort into the bottom corner, after some fine build-up play which twice involved the hugely impressive Van Persie, was the least the hosts deserved for their second-half dominance.
While the Baggies played with plenty of effort and endeavour throughout, and could consider themselves unfortunate to be trailing 2-0 to the only two chances of the first period, they can have no argument with the final result.
Lone forward Simon Cox was lively and dangerous but lacked support and their only effort on target did not come until the 86th minute when Steven Reid's header was easily saved by home keeper Wojciech Szczesny.
Graham Dorrans also twice scuffed low efforts wide after the interval but the second half was a procession of Arsenal attacks as West Brom's solid resistance was broken.
The platform was laid before the break when Van Persie followed up from close range after Theo Walcott's initial shot from Arteta's pass was saved.
And, following Alex Song's cross-field pass, the excellent Vermaelen added a second from Van Persie's exquisite cut-back.
The Gunners, whose last league outing was their stunning win over Chelsea, completely dominated after the interval with Aaron Ramsey and Arteta bossing the midfield.
Belgian centre-half Vermaelen - buoyed by his first goal in almost two years - nearly made it 3-0 soon after the break but his header from Van Persie's corner, went a fraction wide.
Gervinho, Ramsey and Song also all went close to adding to the lead before Arteta's strike brought Arsenal's 13th goal in their last four league wins over Stoke, Bolton and Chelsea.
Arsenal manager Arsene Wenger:
"The spirit of the squad was right from the first to last minute. We worked well together and I always was positive with the team because one month ago we were in a very bad situation.
"You felt there is a desire to do well and now it goes better it is still there. This team wants to improve, wants to work hard and wants to get better and better. That is the most satisfying aspect.
"They didn't switch off when they led 2-0 and that is not always the case. Overall it was a controlled performance. We had complete domination.
"We are getting stronger. We scored five goals last week, three goals today and didn't concede, so overall it is a very positive afternoon."
West Bromwich Albion boss Roy Hodgson:
"Arsenal deserved to win. They played very, very well. The second goal came at the wrong time and at 2-0 with Arsenal in their current mood and form, they were able to play on that and relax. But we stuck to our guns but we lost to the better team.
"We put in one hell of a shift and I thought we had to because we were up against a very good Arsenal team in form, who were rampant.
"You could accuse of lacking a bit of quality at times, you could accuse us of, in the first half, playing the ball forward too early. You could accuse us of those things and I might agree with you, but one thing I certainly will not agree with you is that the players did not put in a shift."