All golfers had until 5 p.m. ET Tuesday to decide whether to participate in the tournament.
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Now, Woods has until 8:35 a.m. ET on Thursday to register, after members of Woods' team asked the PGA for an extension. He is scheduled to tee off at that time alongside Phil Mickelson and Padraig Harrington.
Woods, a four-time winner of the PGA Championship, withdrew from the final round of the WGC-Bridgestone Invitational on Sunday after re-injuring his back.
His caddie, Joe LaCava, said he is optimistic and hopes that Woods is able to play in the PGA.