Brooks Koepka withdraws from this week's AT&T Byron Nelson

MCKINNEY, Texas -- A week before the PGA Championship, the second major of the season, former world No. 1 golfer Brooks Koepka withdrew from the AT&T Byron Nelson on Wednesday.

The PGA Tour didn't disclose the reason for Koepka's withdrawal. The four-time major champion has had knee and hip injuries the past few seasons.

It is unclear how the latest development will affect Koepka's availability for next week's PGA Championship at Southern Hills Country Club in Tulsa, Oklahoma.

Koepka, who won consecutive PGA Championships at Bellerive Country Club in 2018 and Bethpage Black in 2019, hasn't played since missing the cut at the Masters in early April.

Koepka, 32, had surgery on his right knee in March 2021 to repair a dislocated kneecap and ligament damage. He said the injury occurred when he fell while he was visiting his family in Florida. He competed in the Masters less than a month after the surgery.

It has been an inconsistent season for Koepka, who has missed the cut in six of his 13 tour starts. He had two top-10s and four top-25s when he stuck around for the weekend. He has fallen to No. 13 in the world ranking and 67th in the FedEx Cup standings.