Marcus Bignot's Grimsby ended League Two leaders Plymouth's 14-match unbeaten league run with a 3-0 win at Home Park.
Danny Collins rose above the home defence to head Grimsby into a 1-0 lead just before half time.
Argyle failed to effectively clear a corner from the left and when James Berrett looped a cross to the far post, Collins was first to the ball.
It was a similar story as central defender Collins' looped header enabled striker Omar Bogle to head in Grimsby's second goal in the 62nd minute.
Town top scorer Bogle doubled his tally, sliding in to score Grimsby's third in the 86th minute as torrential rain hammered down.
Argyle's on-loan Reading winger Craig Tanner beat the offside trap midway through the first half but was forced wide by a combination of Town keeper James McKeown and skipper Josh Gosling.
Gosling blocked a goal-bound Tanner strike in the 28th minute while Tanner's next effort - after an exquisite looped pass from playmaker Graham Carey - was deflected over by Grimsby's former Argyle midfielder Luke Summerfield.
Gosling - impressive throughout - made a superb block to deny Carey a minute before Grimsby went down the other end and made it 2-0.