- Giroud heads Arsenal winner (87)
- Foster denies Sanchez from two yards
- Baggies now ninth on 23 points
- Attendance: 59,925 (1,400 away fans)
- Albion Star Man: Ben Foster
ALBION were denied a well-deserved point after a late Olivier Giroud header gave Arsenal all three points at the Emirates.
The hosts started brightly in an open first period with both Granit Xhaka and Giroud firing over from 25 yards in the opening exchanges.
Claudio Yacob was twice on hand to intercept the ball on the edge of the Albion area as the Gooners probed in their search for an opener.
With Alexis Sanchez denied by Ben Foster from inside the penalty area, the Baggies defended resolutely and looked a danger from set pieces.
Petr Cech was called into action on two occasions to punch clear Chris Brunt corners.
But it was Foster who was forced into a fine double save from Alex Iwobi and Sanchez in the 50th minute.
After Iwobi's volley, the Chilean was denied by the Albion stopper from two yards out before rattling the post form the resulting corner.
And the superb Foster produced one of the saves of the season when he tipped a thunderous strike from Sanchez over the bar minutes later.
After surviving an early barrage in the second half, Albion pressed for the opening goal with Salomon Rondon seeing his shot blocked by Gabriel at the near post.
Then Claudio Yacob scooped the ball over from five yards after Cech had spilled a corner.
Arsene Wenger's side pressed for a winner in the closing minutes and Giroud was there in the 87th minute to loop the ball over Foster and win the game.
ALBION: Foster, Dawson McAuley, Evans, Nyom, Yacob, Fletcher (c), Phillips, Brunt, Chadli (McClean 62), Rondon (Robson-Kanu 80).
Subs: Myhill, Olsson, Galloway, Gardner, Morrison.
Arsenal: Cech, Gibbs (Monreal 71), Gabriel, Koscielny, Bellerin, Xhaka, Coquelin, Iwobi (Lucas 71), Ozil, Sanchez, Giroud.
Subs: Ospina, Holding, Reine-Adelaide, Elneny, Ramsey.
Referee: Neil Swarbrick.