The Railwaymen have won just once in 13 games and keeper Ben Williams' first-half blunder left them fighting a rearguard action again in what was, in truth, a must-win game for them at the Alexandra Stadium.
When Chris Lines arrowed in a low shot-cum-cross a minute before the interval, keeper Williams conspired to kick the ball into his own net to gift the Pirates the lead.
It was the culmination of a dreadful first half for the home side which had seen first-team coach Steve Holland forced into two substitutions when centre-half Chris McCready pulled his hamstring and midfielder Ben Rix was stretchered off with a bad facial wound.
Rovers posed all the questions with Rickie Lambert forcing Williams into a low save with a 25-yard drive and David Pipe and Craig Hinton also shooting wide.
Crewe responded after the own goal blow when Michael O'Connor saw his rising drive clawed out of the top corner by Steve Phillips.
But when the Rovers keeper couldn't hold Nicky Maynard's stinging shot, the ball ran loose to Tom Pope, who nudged his second goal in three games as Crewe levelled less than a minute after the restart.
Holland's side were much improved in the second half yet Rovers posed a threat on the break and Andy Williams volleyed an Aaron Lescott cross straight at the keeper from close range.
Danny Coles skied a header over and when Williams dispossessed Gary Roberts and raced away from 40 yards out, he should have restored his side's lead only to place the ball the wrong side of the post.
Crewe threw the kitchen sink in a concerted effort to steal a late win, but were denied by some brilliant saves by Phillips.
The keeper parried an effort from substitute Ryan Lowe and then held on to Pope's shot on the turn. But he was saved by his woodwork in the final minute when Pope curled an exquisite effort against the far post.