Billy Kee’s second half penalty gave the Lancashire club the lead, before they deservedly added a second through Sean McConville just moments later.
Kayden Jackson then made sure of the victory – Accrington’s first in five league games – as he added a third to see off his former club.
And, having gone back to basics ahead of the game, Bell was delighted to see his side finally stop their recent rot.
“We’ve been on a poor run of late,” Bell said.
“We haven’t been playing that badly, and you saw the determination today. We felt it in training, and we scored at the right times.
“We had to turn the corner sooner or later because we’re a good team – you don’t get to the top of the league after nearly half a season, and then all of a sudden lose five games on the bounce.
“We knew something was wrong, we’ve addressed it, and you’ve seen the hunger today, and we’ve got to be like that all the time now.
“We stripped it down in training since the defeat to Carlisle. They’ve worked really hard, and we’ve given them jobs to do.
“We matched them up today and said ‘listen, you’ve just got to be better than your opponent.’ We dug in during the first half, and then in the second we kicked on.”
For Grimsby, it’s now four games without a win, and they found themselves outplayed by Accrington for much of the second half.
Boss Russell Slade admitted his side had been second best, but felt slightly aggrieved by the awarding of Stanley’s penalty.
“Accrington were the better side,” Slade said.
“They were a bit better than us in the first period, and then they got the first goal in the second.
“In these games, they come thick and fast. The first goal was very important, and they got that, it’s come from a very soft penalty in all fairness.
“But they deserved their win in the second half. They performed very well, and we weren’t at our normal level which we’ve put together over the last four or five weeks.
“We talked about the first goal being an important one, and actually I thought we’d started the first five minutes of the second half okay, we looked to have a bit of control.
“But it’s those decisions, those moments where you can’t switch off, and we’ve not dealt with a defensive situation, we’ve not tied up quickly enough to stop them, and then the referee’s given a penalty. I thought it looked very soft.”
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