Tony Crane scored against his former club as Grimsby secured a vital win at home to Wednesday.
Crane made the Owls pay when he headed home the Mariners' second goal from an
Iain Anderson cross.
Grimsby had taken an early lead when recalled striker Darren Mansaram bundled home a Phil Jevons cross.
Wednesday had striker Guylain Ndumbu sent off just before half-time after he
kicked out at Jevons and in the second half they failed to breakthrough.
Grimsby: Fettis, Ford, Crane, Edwards, Crowe, Anderson,
Lawrence, Coldicott, Jevons, Rankin, Mansaram. Subs: Parker,
Antoine-Curier, Rowan, Campbell, Thorrington.
Sheff Wed: Pressman, Geary, Dean Smith, Bromby, Barry-Murphy,
Cooke, Mustoe, McMahon, Brunt, Proudlock, Ndumbu-Nsungu. Subs:
Chambers, Shaw, Tidman, Olsen, Wood.
Referee: P Dowd (Staffordshire).