Grimsby won 2-0 at Plainmoor to extend Torquay's losing streak to five matches in League Two.
Nicholson own goal and Sweeney free-kick seals win for Mariners
Grimsby made it back-to-back wins in League Two thanks to Peter Sweeney's second-half free-kick and an own goal from Gulls left-back Kevin Nicholson.
The Mariners extended Torquay's losing streak to five matches with the victory, which came after Mike Newell's side defeated Hereford last time.
The first chance came when Mark Ellis, called up for his Football League debut, tested Grimsby goalkeeper Josh Lillis with a seventh-minute header from Nicholson's corner from the left.
The visitors then countered, with the recalled Jamie Clarke teeing up fellow midfielder Sweeney for a 25-yard drive in the 12th minute that had on-loan Southampton goalkeeper Michael Poke at full stretch.
Lillis then thwarted home striker Elliot Benyon, while Chris Hargreaves looped a header just over before Adrian Forbes' shot was superbly blocked by Chris Todd in first-half stoppage-time.
Ellis went close to opening the scoring at the start of the second half with a far-post header that flew just wide from Nicholson's free-kick from the left.
A few seconds later Nicholson inadvertently sliced the ball over his own keeper under pressure from Grimsby substitute Peter Bore to put Grimsby ahead.
The Mariners then doubled their advantage in the 65th minute when Sweeney's superbly-struck free-kick from 25 yards flew in.
