(McKinney, TX) -- The PGA Tour is in the Lone Star State for this weekend's AT&T Byron Nelson at TPC Craig Ranch. K.H. Lee is the defending champion after winning last year's tournament with a 25 under par. Lee will be joined by Jordan Spieth and Scottie Scheffler for the first round, which gets going on Thursday. Brooks Koepka will not be participating in the tournament after he withdrew from the event on Wednesday. The PGA Tour did not disclose the reason for Koepka's withdrawal. Harry Higgs, Kelly Kraft, and Wyndham Clark will be among the first group of players teeing off the tournament.