Overheard at the Half-Marathon: ‘Wait, Was That Lil Nas X?’

Ahead of one of its signature events, New York Road Runners fielded an unusual email request on Friday night.

The rapper and singer Lil Nas X, who was visiting New York from Los Angeles, had seen some advertisements for the United Airlines NYC Half, a 13.1-mile race that was set to be staged on Sunday morning. And one of his representatives was curious: Did the race have room for one more runner?

“It kind of came out of the blue,” Rob Simmelkjaer, the chief executive of New York Road Runners, said in a telephone interview on Monday.

The nonprofit, which puts on about 60 races each year, including the New York City Marathon, was happy to oblige. It hardly mattered that Lil Nas X, who will turn 25 next month, had seldom run more than three miles consecutively, let alone a half-marathon. Or that he showed up for the race in a pair of Coach high-top sneakers, which are more boot than high-end racing flat.

Accompanied by Roberto Mandje, New York Road Runners’ senior adviser for running engagement and coaching, Lil Nas X was among more than 27,000 finishers, completing the race in 2 hours 32 minutes 53 seconds.

“We would be running and you’d hear someone shout, ‘Wait, was that Lil Nas X?’” Mr. Mandje said in an interview. “So he’d turn around and wave, and they’d freak out.”