Arsenal's top-four hopes suffered another blow as they lost 3-1 to West Bromwich Albion at the Hawthorns against a backdrop of planes with banners calling for Arsene Wenger to leave and another supporting him.
The hosts made a good start with Allan Nyom breaking down the left and beating three men before flashing a ball across the face of the Arsenal goal, and minutes later James McClean drew a good save from Petr Cech.
From the resulting corner Craig Dawson beat Laurent Koscielny in the air to head West Brom in front on 12 minutes.
But Arsenal were soon back on level terms. Alexis Sanchez took advantage of bad marking on 15 minutes with a powerful effort from close range.
Theo Walcott and Darren Fletcher were both denied by good saves from Ben Foster and Cech before the Arsenal goalkeeper went down injured, to be replaced by David Ospina in the 38th minute.
Hal Robson-Kanu came on for Salomon Rondon in the 54th minute and restored the hosts' lead with his first touch. A defensive mix-up saw Ospina's attempted clearance fall straight to the West Brom man's feet allowing him to poke home from close range.
And with 15 minutes remaining Dawson added a third with a goal similar to his first, heading in from a corner.
The result leaves Arsenal fifth and five points behind fourth-placed Liverpool, but with a game in hand.