Colchester manager John Ward was full of praise for opponents Rochdale after Ian Henderson stepped off the bench to snatch the Us a 1-0 home win.
Henderson planted a shot past Dale goalkeeper Owain Fon Williams from close range with four minutes to go and although Dale substitute Jean Louis Akpa Akpro rattled the crossbar late on and Nathan Clarke headed Joe Thompson's effort on to the woodwork, Colchester held out.
Ward said: "I thought we were going to see a draw, but for us to get the break at the end, I'm delighted because we've played really good opponents in Rochdale.
"Credit to them and credit to Keith for the way he has got his team playing this season. It took us 87 minutes of really hard work, tactical awareness and discipline to find the opening.
"We had talked about being patient and organised and I really enjoyed the tactical work with Keith, because his team play with good shape and some good players.
"We got the break at the end and I'm delighted with the way my team went about it. Like all games it could have gone either way and both goalkeepers made good saves. We've beaten a very good team who have the second best defensive away record in the division, so it was never going to be a 4-4, exciting, end-to-end game."