Making his first league start since the season’s opening day, Alex Oxlade-Chamberlain scored both goals in the second half to send Arsenal two points above Manchester City, who host third-place Chelsea on Monday.
After a frustrating firs half, Arsenal increased the tempo after the interval and went ahead via Alex Oxlade-Chamberlain’s neat finish after a fantastic pass from Santi Carzola.
Yannick Bolasie missed a great chance to equalise for Tony Pulis’ men as his header was blocked by Wojciech Szczęsny. Oxlade-Chamberlain then put the result beyond doubt 17 minutes from time with a low finish into the bottom right-hand corner after a good give and go with Oliver Giroud.
Earlier in the day, Liverpool were held at West Brom. Luis Suárez and Daniel Sturridge combined for the first-half opener, with the England striker tapping in from close range.
However, the Merseyside club were pegged back when Victor Anichebe pounced on a horrific Kolo Touré pass and drove a low shot into the bottom left-hand corner from the edge of the area.