Updated

(SportsNetwork.com) - Dustin Johnson reportedly failed a third drug test and that is apparently the reason he is taking a leave of absence from the PGA Tour.

According to a Golf.com report, Johnson has failed three drug tests, one for marijuana in 2009 and two for cocaine -- first in 2012 and then earlier this year. The latter caused him to be suspended for six months.

In 2012, Johnson missed the Masters and was out for nearly three months. At the time, it was announced that he injured his back while lifting a jet ski, but Golf.com cited a source in its report as saying Johnson was serving a suspension for a failed drug test.

The PGA Tour does not announce suspensions, but in a brief statement on Thursday stated, "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."

Johnson, an eight-time winner on the PGA Tour, released a statement on Thursday that read in part, "I am taking a leave of absence from professional golf, effective immediately. I will use this time to seek professional help for personal challenges I have faced.

"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."

The 30-year-old had withdrawn from the WGC-Bridgestone Invitational earlier in the week. The PGA of America announced that Johnson will not take part in next week's PGA Championship or the Ryder Cup in late September.

Johnson is fifth on the United States Ryder Cup points list. With him not playing the event, that means whoever is ranked 10th on the points list as of Monday, Aug. 11, will make the team automatically.