Mikel Arteta’s side remain in 10th position in the league but could end up in the bottom half if results don’t go their way.
Villa recovered from their midweek loss against West Ham United and are five points off the top four places with a game in hand.
Villa broke the deadlock inside the opening two minutes after some poor Arsenal defending which resulted in Watkins’ deflected strike going into the back of the net.
Partey limped off after the hour mark and Jack Grealish almost doubled Villa’s lead but Ryan produced a fine save to deny him.
Arsenal almost equalised late on but Martin Odegaard‘s close range shot blazed over the bar.
Watkins also saw a strike go just past the post in the latter stages of the game but Villa survived to secure an important victory.