Max Watters 16th goal of the season handed Crawley all three points with a 2-1 win at Leyton Orient.
The visitors went in front after 15 minutes when Town's Sam Matthews drilled in a powerfully hit free-kick from the right and Orient central defender Josh Coulson headed the ball into his own net.
The home side restored the status quo in the 41st minute when James Brophy raided down the left and picked out Jobi McAnuff, whose fierce shot was deflected by Tim Dallison-Lisbon past his own keeper.
Both McAnuff and Brophy had penalty claims turned down by referee Scott Oldham after the break but Crawley always posed a threat, with Tom Nichols causing problems for the home side.
First, he curled an effort narrowly over the bar and then hit a shot from the edge of the penalty area that struck the crossbar.
But it was leading marksman Watters who provided the clinical finish eight minutes from time. Substitute Ashley Nadesan broke into the box and picked out Watters, who drilled the ball low into the net.