An inspirational display by skipper Phil Mason helped the Ducks to record their first win in 10 games. It was a poor first half show by United with only one shot on goal as they struggled to contain their Essex hosts.
Canvey went ahead after 26 minutes when Neil Gregory converted Chris Duffy's cross from close range, but United levelled in the first minute of the second half when Scott Honeyball headed in at the far post from Mason's free kick.
Canvey regained the lead on 52 minutes when Steve Tilson's 20 yarder was deflected past Gary Phillips, but United levelled again on 80 minutes when Mason curled a superb 25 yard free kick over the wall past keeper Ashley Harrison.
The comeback was complete on 86 minutes when Mason's good run set up Danny Hutchings to fire home the winner and take United out of the relegation zone.
