The Mariners were stunned after a tired looking second half display at The Checkatrade Stadium this afternoon.
Marcus Bignot named the the same starting Xl that finished the midweek draw with Carlisle United, with Dominic Vose and Craig Disley keeping their places in the Town midfield.
The back four (unchanged) of Zak Mills, Josh Gowling (c), Danny Collins and Danny Andrew. Kayden Jackson partnered Omar Bogle in the Mariners' attack.
Both sets of supporters impeccably observed a minutes silence before the game for the late and great Paul Futcher.
There will probably no complaints about the scoreline as a tired looking second half performance sent the Mariners crashing to the first defeat under Marcus Bignot.
The second half completely belonged to the hosts and the crossbar and two notable saves from James McKeown denied The Reds further goals.
All that after the Mariners dominated the first half. But Town did go behind on 31 minutes. With Town attacking, Crawley broke away down the right, the ball was switched to James Collins, as Gowling came in he slipped, giving Collins time to switch the ball onto his right foot before rolling the ball past McKeown.
That looked like it was going to be the half time score-line. But in stoppage time at the end of the first half, Bolarinwa skipped away down the right, before his cross deflected up off a defender for Omar Bogle to head home to make it one a piece.
It looked like Town would go on from there and, at the start of the second half, Bogle put a 35 yarder onto the roof of the Crawley net.
But that was about that and all of a sudden Crawley came to life. Collins broke away down the right, before pulling the ball back for Roberts to steer the ball inside the post.
James McKeown was at his best to deny the home side from a corner, getting in the way of a point-blank effort.
Then, with Danny Collins off receiving treatment, the home side were awarded a corner. Roberts' in-swinging dead-ball kick seemed to go straight in at the near post, giving The Reds a seemingly unassailable 3-1 lead.
That seemed to be that, but Omar Bogle had other ideas and his superb 25 yarder sailed past Morris to give the visitors some hope with five minutes of injury time to play.
And there was still time for Tom Bolarinwa to salvage something for the Mariners but the Red's keeper stood up well to deny the frontman.
Bogle's brace now pushes back to the top of the Sky Bet League Two scoring chart with 16 goals to his name.
With no competitive game scheduled for next week, the Town boss has arranged a behind closed doors game.