Arsenal have now moved up to fourth place in the Premier League, following Chelsea’s 4-0 defeat at Bournemouth.
The Gunners’ 2-1 win over Cardiff City on Tuesday, ensured they stayed three points behind their London rivals.
However, it got better for Unai Emery’s men at the Vitality Stadium, thanks to Joshua King’s brace.
David Brooks and Charlie Daniels also got on the score sheet, as the Cherries recorded a famous victory.
In the other matches played on Wednesday, Crystal Palace were held to a 1-1 draw with Southampton.
Tottenham Hotspur came from behind to beat Watford 2-1 and Liverpool were held to a 1-1 draw by Leicester City, to increase the gap at the top between them and Manchester City to five points.