The PGA Tour say that this week's Travelers Championship will go ahead, despite Webb Simpson become its latest high-profile withdrawal.
Last week's winner at the RBC Heritage has produced two negative test results this week, but says he's exercising an "abundance of caution".
His withdrawal follows those of Graeme McDowell and Brooks Koepka after both of their caddies tested positive for COVID-19.
"In the last 24 hours, I have had a family member test positive for COVID-19," Simpson said in a statement.
"While my tests this week were negative, I feel like it is my responsibility to take care of my family and protect my peers in the field by withdrawing from the Travelers Championship.
"I am going to return home to Charlotte and quarantine under CDC guidelines, and I look forward to returning to competition after that time period."
Out of 2,757 tests conducted across all PGA Tour events this week, there have been seven positive results.
However, Tour commissioner Jay Monahan confirmed an expansion of testing on Wednesday.
Swing coaches and instructors will also be subject to testing, and there will be an increase in the number of tests for players who plan to travel from tournament to tournament on the circuit’s charter flight.
Commissioner Jay Monahan addresses the media to provide an update on COVID-19 testing results @TravelersChamp. https://t.co/vWSpaZcH2S
— PGA TOUR (@PGATOUR) June 24, 2020
Monahan also said players have been reminded to adhere to social distancing guidelines while away from the course.
"All of us have an extraordinary responsibility to follow those protocols. For any individual that does not, there will be serious repercussions," he told a videoconference.
"Everybody knows and needs to know that our future, our ability to sustain this business and to impact the communities where we play and to create so many jobs is contingent on our ability to follow those protocol."
Despite there being seven positive tests in one week, and several withdrawals from events in Cromwell, Monahan says the tour will continue.
"This has always been about a sustained return,” Monahan said.
"I am very comfortable, very pleased, very confident in the health-and-safety program that we have, even though we've had positive tests.
"In this world, I think that that's an expected outcome. We've learned a lot.
"We never said we were perfect. We just have to keep getting better and better and better as we go forward, but it is not from a lack of attention."