Mark Bonner reflected on the “mad story” that led to him becoming a promotion-winning Cambridge head coach.

Bonner watched United growing up and worked his way through the ranks before taking charge last March, and a 3-0 victory over Grimsby secured second place in League Two and promotion to the third tier, where they last played in 2002.

Liam O’Neil’s volley in the first half set Cambridge on their way, before Wes Hoolahan and the division’s player of the year Paul Mullin struck after half-time.

Promotion ends a seven-year stint in League Two, while at the other end of the table Grimsby finish the season bottom and return to the Vanarama National League after five years.

Mullin finishes the campaign as the division’s highest scorer with 32, breaking the fourth-tier record for goals scored in a season since it was rebranded League Two in 2004.

“It’s massive,” declared Bonner afterwards. “We are competing well above where we were expected to be, where our resources have been this season.

“We’ve got really talented players, a couple of individuals who have done exceptionally for us. The unity and togetherness of the side’s been outstanding.

“Any team that gets promoted deserves huge recognition for that because it’s so hard and so demanding. This group, this year especially, they’ve done it and they’ve bounced back brilliantly all the time. I’m absolutely thrilled for them and I hope they have a great few days.

“It’s been edgy and nerve-wracking but the boys held their nerve. We ended up getting a nice result and the day became fairly comfortable in the end which was important for us.

“It’s moments like this you think that 16 years ago we got relegated from the Football League. We’ve come a long way since then. I was a season-ticket holder 22 years ago watching us play Brentford on the last day of the season and whoever won won the league to get back into League One. That’s the last time we were there.

“So to now be on the touchline and taking that team is a bit of a mad story. I don’t allow myself to think about it too much, you’ve just got to enjoy those moments as much as you can.”

Grimsby boss Paul Hurst offered his compliments to Cambridge while also seeking to rebuild his side as they return to the National League.

“A big congratulations to Cambridge,” he said. “They, probably against the odds somewhat, have won promotion, and credit to them.

“The table doesn’t lie after that many games, so a big well done to them. It shows what can be achieved when you’ve got a good team spirit, a goalscorer of course. They were excellent.

“As much as the scoreline suggests a heavy defeat, it was three set-plays. They were poor, poor goals form our point of view. There wasn’t enough edge to us and Cambridge had more of that.

“Now it’s all about moving forward. I’ll be speaking to the players when I feel it’s right and letting them know the plans for each of them as individuals.

“The difference now is we’ll have one more week off and it’ll mean a week longer pre-season for us, so that can be positive as we have an extra week with the players.”