Johnson had bowed out of the WGC-Bridgestone Invitational under way at Firestone Country Club. Now he will also miss next week's PGA Championship at Valhalla and the Ryder Cup in September. Fifth in the points standings, Johnson was a lock to make the U.S. Ryder Cup team.
"I will use this time to seek professional help for personal challenges I have faced," Johnson said. "By committing the time and resources necessary to improve my mental health, physical well-being and emotional foundation, I am confident that I will be better equipped to fulfill my potential and become a consistent champion."
Johnson asked for privacy during his absence.
In a statement, the PGA Tour said, "We have nothing to add to Dustin's statement. But wish him well and look forward to his return to the PGA Tour in the future."
Fellow players such as Rickie Fowler, Zach Johnson and Justin Rose were caught off guard by the announcement and expressed their support for Dustin Johnson.