Rory McIlroy and Brooks Koepka revealed they had both been around Nick Watney before the American's positive test for coronavirus.
Watney withdrew from the RBC Heritage before the second round on Friday after returning a positive test for COVID-19.
McIlroy, who is tied for 45th at five under, said he had exchanged texts with Watney after the pair were on the putting green together.
"Nick texted me actually because we had a chat on the putting green before I went out to play, but we were at a distance," the world number one said.
"He was just saying, 'Look, I hope I didn't get too close to you.' He feels badly that he was here today at the golf course. I said, 'It's fine, you never know.' I said to him, 'If I was in your position, I probably would have been here too. Look, at this point, you just have to concentrate on getting better and getting healthy.'
"But it sucks for him especially. You know, if you contract it, that's fine, but then it's the fact that who have you come into contact with, and who you might have exposed and stuff.
"Look, we're still in the middle of a pandemic. It's not as if this thing is over, so we all just have to stay vigilant and keep our distance and wear our masks if we're going out in public and keep washing our hands."
Koepka, who carded a five-under 66 to be three shots behind leader Webb Simpson, said he too had spent time with Watney before his round.
"I found out when we were playing 17, I think Daniel Berger told me," he said.
"I don't know too much about it, but I saw him this morning. I was right next to him in the parking lot."
There have been more than 8.7 million confirmed cases of coronavirus, with the death toll exceeding 462,000.