If only it had been a missed connection.

Stepping out of a cab at College St. and Dovercourt Rd. recently, a man opened the door of a taxi cab directly into the path of a female cyclist, sending her tumbling to the ground.

The infamous “door-prize” is a much-dreaded threat for cyclists in the city, but the woman apparently dusted herself off, said she was fine, and even admitted she had once doored a cyclist herself.

But fearing he did not sufficiently express his regret, the man decided to take to Craiglist’s Missed Connections board to say it once and for all: “I was stupid, stupid, stupid and I should’ve looked out and checked that there wasn’t anyone behind me.”

“If I didn’t apologize enough then and there, I wanted to do so now in and what is probably the only public forum appropriate to do so,” he wrote in a post published Tuesday.

Contacted by the Star Tuesday, the man declined to comment other than to say he had not yet heard from the cyclist — though he did have an inquiry from another cyclist who had also been doored.

In the posting — titled “(I) probably shouldn’t have doored you” — he said he is also a cyclist who has been knocked off his bike, and said getting doored “is a fear that hovers around us at all times when we’re biking on busy streets.”

“I’m sorry I made you fall … . It sucks, I sucked,” he said, adding that if there was any damage to her bike, he would pay to fix it.

The unlikely post on Missed Connections — a board usually reserved for romantics wanting to reconnect with a fleeting love interest — was getting love of its own from the Twitterverse Tuesday.

“Stand up guy!” wrote @JdotRaymond.

“Awesome apology,” said @deptofhighfives.

tweeted @frankie_felony.