Campbell left the Stags last month - having managed to keep them in League Two against massive odds.
“I remember being with my wife after we stayed up and just bursting out crying," he recalled to the Mirror.
“It was so tough. It was tears of relief.
"We did it, the pressure, I'm an emotional guy when it comes to football. I love competing. I love the tactics, I love the strategy, I love it when a team comes together… The A Team and all of that! I've got that in my system."