Bobby Grant gave referee James Adcock little alternative but to brandish the red card following a reckless challenge on former Dale defender Rory McArdle 35 minutes into the clash.
"No disrespect to Bradford because I thought they were smashing and started really well, but I thought we defended magnificently and coped really well after Bobby's sending off," said Coleman.
"There weren't too many heart-in-your-mouth moments for us. Okay, Joe Rafferty kicked one off the line late on and they smashed one straight at Josh Lillis. But there were not too many scares, we competed throughout and I don't think anyone could begrudge us a point.
"We dropped a bit deeper at times, but that's only natural for a side down to 10 men trying to protect their clean sheet.
"But they threw bodies on the line and when you consider three of the back four are under 20 years old, it was a great achievement."