HILTON HEAD ISLAND, S.C. – The WHOOP strap has become a fixture on the PGA Tour, with players using it to collect physiological data to help them analyzes strain, recovery and sleep on an athlete’s body. Nick Watney’s strap might also have played a key role in detecting the Tour’s first positive COVID-19 test.

Watney became the first player to test positive for coronavirus on Friday at the RBC Heritage. According to a Tour press release Watney “felt symptoms consistent with the illness” early Friday but the circuit didn’t specify what symptoms.

“Nick said the thing that got him yesterday morning was he wears a WHOOP strap,” said Rory McIlroy, who traded text messages with Watney after he withdrew.

“One of the big telltale signs that they've found over the last few weeks, they've done studies where, if your respiratory rate goes up during the night by more than two breaths per minute, that's sort of a telltale sign that you might have something.”

“It was actually his WHOOP that told him his respiratory rate went up, and that's why he thought maybe I could have it.”

McIlroy, who spoke briefly with Watney on Friday on the putting green before he withdrew but wasn’t required to take a coronavirus test as a result of contact tracing, said Watney’s plight has made everyone more aware of the potential for the virus.

“I looked at mine [WHOOP strap] this morning just to see what my respiratory rate was and make sure it was OK, and you go from there,” he said. “I feel totally fine.”