Patrick Reed is currently in hospital recovering from bilateral interstitial pneumonia, according to Golf Channel's Todd Lewis.
Reed, 31, withdrew from the Wyndham Championship last week and then again at this week's Northern Trust with an ailing left ankle.
.@PReedGolf has been in a Houston area hospital since Friday morning after being diagnosed with bilateral pneumonia. Reed is improving and hopes to be released soon. He will not play the @BMWchamps this week. Below is a statement from Patrick Reed. More details on @GolfCentral. pic.twitter.com/AXXdH5har2— Todd Lewis (@ToddLewisGC) August 23, 2021
Reed reportedly travelled home to Houston on Wednesday and then had his ankle examined by a doctor.
However, he was then later diagnosed with bilateral interstitial pneumonia, which is also known as double pneumonia - an infection in both lungs that can cause inflmmation and scarring.
The 2018 Masters champion has since been admitted to Houston Methodist Hospital.
"I’m on the road to recovery," said Reed in a statement.
"Once I’m cleared from the doctors, I look forward to returning. I wish you all the best and I can’t wait to get back out there."
Reed has confirmed he will not be playing in next week's BMW Championship, and he would appear a huge doubt to compete in the season-ending 30-man Tour Championship, especially as he is expected to fall to 26th in the standings after the Northern Trust.
"It got really bad very quickly," Reed’s wife Justine told Lewis.
Reed will now not be able to automatically qualify for the United States Ryder Cup team, and he will now need to rely on one of Steve Stricker's six captain picks.