A hat-trick from in-form forward David Johnson condemned Grimsby to their sixth consecutive defeat and keeps them rooted to the foot of Division One.

Johnson took his tally for the season to nine as he headed Forest into a 17th-minute lead.

After Tony Gallimore was sent off following an incident with Eugen Bopp, Johnson secured the points with a late penalty and a well-taken third.

Within the first five minutes, Tuesday's hat-trick hero Marlon Harewood had fired wide from the edge of the box and blazed a shot over the crossbar.

Eoin Jess had also forced a fine stop from goalkeeper Danny Coyne with a 25-yard drive.

Forest were well on top and their efforts were rewarded when Johnson broke the deadlock.

Town keeper Coyne looked favourite to gather Mathieu Louis-Jean's right-wing centre, but Johnson managed to steal in and head home.

After the restart Grimsby started brightly and player-manager Paul Groves sent a header wide after 52 minutes, while Steve Kabba also fired wide and then had a shot saved by DarrenWard soon after.

But Grimsby's hopes began to recede when Gallimore was shown a straight red card for a bad challenge on Bopp.

Johnson was unlucky to see two shots clear the crossbar, but he did double Forest's advantage from the spot in the 86th minute after he had been brought down by Groves.

And, just to compound the Mariners' misery, he coolly slotted home his third in injury time.

Grimsby: Coyne, McDermott, Groves, Chettle, Gallimore, Campbell, Coldicott, Pouton, Barnard, Kabba, Robinson.
Subs: Ford, Allaway, Mansaram, Rowan, Cooke.

Nottm Forest: Ward, Louis-Jean, Walker, Dawson, Brennan, Williams, Bopp, Prutton, Jess, Harewood, Johnson.
Subs: Hjelde, Lester, Roche, Doig, Reid.

Referee: G Laws (Tyne & Wear).