(CHICAGO) Off-duty, clad in a Hawaiian shirt and driving south on Damen Avenue with his 6-year-old boy, Chicago Police officer Sean Hayes suddenly found himself back on the job Sunday morning.

The 16-year CPD veteran noticed a man near Roscoe who looked puzzled and hurt. He stopped to check on him, and that’s when he noticed the man was bleeding heavily from his neck.

Moments earlier, the 21-year-old man had crashed his bicycle into a car door that had been opened in his path while he was traveling north on Damen. The edge of the door frame punctured the man’s neck, Hayes said. So the off-duty officer grabbed some medical equipment out of his car and put his specialized training to work, applying pressure to the cyclist’s neck with a bandage until the Chicago Fire Department arrived.

“He was looking for answers,” Hayes said of the victim. “‘Am I hurt? Am I going to be OK?’ I said, ‘Yeah, you’re gonna be fine.’”

The motorist who opened her car door in the cyclist’s path was hysterical, Hayes said. He said he gave her a “difficult bandage for her to open up” while he turned his attention to the cyclist.

The cyclist was taken to Illinois Masonic Hospital, where he was reportedly in serious but stable condition. Chicago Police said the crash remains under investigation.

Meanwhile, Hayes said his son was pretty impressed.

“My son thought it was great,” Hayes said. “Daddy’s a hero.”