Nigeria international Alex Iwobi was on target for Arsenal on Tuesday night but his effort was unable to avert a shock defeat for the Gunners at the Emirates stadium against Watford FC.
Quick-fire goals from Yohannes Kaboul and Troy Denney saw Watford take a surprising 2-0 half time lead, and while Iwobi pulled one back for Arsenal in the second half, it could not save the day for the stuttering Gunners.
Elsewhere, Liverpool and Chelsea shared the spoils at Anfield as their game ended in a 1-1 draw.
Tottenham Hotspur failed to benefit from dropped points by Chelsea as they also played out a barren draw against relegation threatened Sunderland.
Chelsea still have a nine point advantage at the top having amassed 56 points from 23 games.
It was however a good night for Swansea City who gave their survival chase a big boost with a 2-1 win over Southampton.
Crystal Palace also got a win over AFC Bournemouth as battle for survival in the EPL enters a new gear.