Crystal Palace made up for their 5-2 drubbing at Grimsby last season with a 4-1 demolition of the relegation-threatened Mariners.

The Eagles were 3-0 up at half time thanks to strikes from Wayne Routledge, Noel Whelan and Julian Gray and, although Grimsby pulled one back through Steve Chettle, Dougie Freedman put the icing on the cake with the fourth.

Palace boss Trevor Francis revealed that last season's hammering played a part in motivating his side.

"That was very much on our minds as we left the dressing room," he said. "We did not allow it to become a battle because we kept on scoring.

"It would have been a battle if we had not been so clinical in our finishing. Goals change games.

"The second half was not quite so good and we had to do more defending. When they scored it set us back a bit.

"But then Dougie Freedman had two good chances before he clinically finished another one, which was the most difficult of the three. At 4-1 we did not have too many worries."

Grimsby boss Paul Groves refused to throw in the towel despite the defeat sending his side to the bottom.

"We have to keep believing. We must keep going," he said.

Groves revealed that his squad had been laid low by a sickness bug and one of the victims, Tony Gallimore, had to play because there was not another left-back at the club.

"But that is no excuse for our first half performance," he said.

"All people will look at at the end of the season is our position in the league. We still have a chance. There are still points on the table and we will keep going to the end."

Grimsby spurned the chance to take an early lead when Stuart Campbell failed to convert a cross from Michael Boulding inside the six-yard box.

They had a better chance in the 15th minute when Michael Keane was played through by Campbell but shot early and wide when he had time to take the ball on.

It proved costly for two minutes later Palace went ahead. Gallimore lost possession to Wayne Routledge and the mid-fielder then outpaced the full-back before clipping a right-foot shot past the advancing Danny Coyne.

Palace made it two in the 34th minute with a goal of real simplicity. Routledge's cross from the right was headed back at the far post by Gray and Whelan headed home from just a couple of yards.

A minute later it was three. Keane's hurried clearance only reached the unmarked Gray and he drilled a left-foot shot into the far corner.

Grimsby gave themselves hope with a goal three minutes after the break. Veteran defender Chettle got on the scoresheet when his header from Campbell's cross slipped through the fingers of Alex Kolinko and over the line.

And they should have made it two four minutes later when Boulding picked out Darren Mansaram in the box but the young striker fired straight at Kolinko.

Grimsby were unable to sustain their comeback and Palace substitute Freedman squandered two good chances. First he headed wide from Danny Butterfield's cross and then he poked a shot inches past the post.

The Mariners went close when Campbell volleyed just past the far post.

In the last minute Freedman atoned for his earlier misses by firing right-footed past Coyne from Butterfield's cross.