Published: 16:40, 18 March 2017
Relegation fears increased for the Gills after another heavy defeat.
Goals from Nathaniel Mendez-Laing and Ian Henderson put the hosts in charge at the break, scoring either side of a Josh Parker effort.
Callum Camps made it 3-1 and a red card for Zesh Rehman left the Gills with it all to do. The hosts wrapped it up with a fourth on 90 minutes.
The Gills dropped to 18th in the table after the loss, four points off the drop zone.
There were two changes in the Gillingham starting XI, with young central defender Mitchell Dickenson in for his first league start, replacing injured Deji Oshilaja.
Up front Parker was handed a start in preference to Joe Quigley.
Gillingham started the afternoon just four points off the relegation places in League 1 and were hoping to shake off their midweek drubbing against Bolton. But for the second time in five days they conceded four.
The Gills had managed only two clean sheets in the league all season, one of those coming against Rochdale. It wouldn’t be replicated on Saturday as Ady Pennock's side conceded with just 10 minutes gone.
Mendez-Laing scored the opener, cutting in on his left foot to leave the Gills defence exposed, before bending the ball home into the top corner.
The Gills pulled it level with 17 minutes gone and enjoyed a decent spell after Parker's goal. He headed a Mark Byrne cross against a post before finishing with the follow-up.
Cody McDonald was denied by the keeper at the near post after racing onto Rehman’s ball forward and moments later Lee Martin came close to latching onto Parker’s weighted ball through the defence.
That positive approach didn’t last long as Rochdale gradually got themselves back in charge.
Lively forward Henderson twice came close before putting Rochdale back in front. He hit one effort against a post and was then denied by Stuart Nelson before finding the net on 33 minutes. He raced onto Mendez-Laing’s flick before chipping the keeper.
Gillingham had switched from a wing-back formation to a flat back-four early on, but Rochdale kept on the front foot, almost making it 3-1 just before the break. Nelson turned Mendez-Laing’s shot onto a post after the winger had charged through the weak Gillingham defence.
Hopes of a comeback faded as Rochdale scored again four minutes after the restart and it came from a Gills corner. The ball was cleared to Mendez-Laing and he ran half the length of the pitch before picking out Camps for an easy finish.
Dangerman Mendez-Laing again tormented the Gills defence, this time cutting in on his right foot, forcing Nelson into making a diving save.
The Gills were reduced to 10 men for the final half hour after Rehman picked up two yellow cards, both for fouls, in the space of eight minutes. There was no argument over the second booking, after a high challenge left Mendez-Laing in a heap.
A reshuffle from the Gills bench led to Elliott List joining McDonald up front and Scott Wagsaff playing right-back in a 4-3-2 formation. The Gills were a threat with nothing to lose.
Young striker Greg Cundle went on for the last few minutes, for his first league appearance, but there was to be no comeback for the Gills.
Rochdale made it 4-1 in the 90th minute. Home sub Peter Vincenti got clear of Dickenson and finished well after rounding Nelson.
Rochdale: Logan, McNulty. Canavan, McGahey, Lund (Rathbone 76mins), Andrew (Vincenti 76mins), Camps, Mendez-Laing (McDermott 81mins), Allen, Bunney, Henderson. Subs not used: Wilson, Owusu, Morley, Kitching.
Gillingham: Nelson, Ehmer, Dickenson, Rehman, Martin, Muldoon, Byrne, Hessenthaler (Wagstaff 62mins), Dack, McDonald (Cundle 82mins), Parker (List 65mins). Subs not used: Holy, Osadebe, Quigley, Mbo.
Attendance: 2,582 (176 away)
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