Defenders Julian Bennett and Neil Emblen both found the net as Walsall came from behind to earn a 2-1 win over Colchester United at Bescot.
Walsall dominated the match for long spells and manager Merson twice struck the cross bar from distance. Jorge Leitao somehow missed an empty net following a defensive mix up and Matty Fryatt was denied at point blank range by keeper Dean Gerken.
Totally against the run of play, Colchester opened the scoring after 71 minutes. Richard Garcia latched onto a Stephen Hunt cross to fire past debutant Joe Murphy, who later left the field injured.
Two minutes later, Julian Bennett powered a header from a Paul Merson corner into the net to make the score 1-1. Then with six minutes to go, Bennett flicked on another Merson set piece and Emblen applied the finishing touch to move Walsall out of the relegation zone.