Brooks Koepka and Graeme McDowell are the latest players to withdraw from this week's Travelers Championship after their caddies both tested positive for coronavirus.
And with Cameron Champ also pulling out and reports of infections in the families and entourages of other pros, the PGA Tour's celebrated resumption is coming under intense scrutiny.
As world No 4 and four-time Major-winner, Koepka's withdrawal is a particular blow. Ricky Elliott, his bagman, was discovered to have contracted the disease when being tested after McDowell pulled out.
It is understood that Elliott, a long-time friend of McDowell's, joined his fellow countryman and his caddie Ken Comboy in a six-hour car trip from Orlando to South Carolina last Monday.
Comboy believes he picked up Covid-19 on a commercial flight following the Tour's first restart in Fort Worth in Texas two weeks ago. After last week's first round of the RBC Heritage in Hilton Head - where Nick Watney became the first player to test positive - Comboy began to suffer from a sore throat.
The pair missed the cut and made the 350-mile drive back to Orlando, where McDowell lives. But on Saturday, the Tour informed Comboy he should return to South Carolina to be tested and on Tuesday that came back as positive.
"For the protection of the field and for my own physical and mental well-being, I'm going to take a test tomorrow morning then jump on a private plane," McDowell told Golfweek. "I'm going to get myself out of here, home to Florida and decide whether I need to quarantine myself from my family. We (Kenny and himself) are a close-knit team. We roomed together last week, we spent six hours in a car. He's carrying the virus so in some way I have to be carrying it too."
On Tuesday, McDowell played a practice round with Koepka, who also came into contact with Watney on the day his infection was confirmed. "I'm going to pull out to protect everybody else. I think it's the right thing to do," Koepka said. "I don't want to risk anyone's life."
McDowell sounded a note of caution. "I think we're trying to do our best out here to mitigate the risk but at the end of the day it's impossible to mitigate 100 per cent of the risk," he said. "The bubble is speculative at best. It's hard for the Tour, even with all their resources, to control everyone all the time."
Rory McIlroy is due to tee off his opening round at 12.35pm, alongside Phil Mickelson and Bryson DeChambeau. Shane Lowry is set to play in the threeball behind, with Paul Casey and Patrick Cantlay. (© Daily Telegraph, London)
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