Spieth (66) builds momentum for PGA Championship

After three rounds that largely led to frustration for the world No. 2, Spieth closed with a 4-under 66, his lowest score of the week at Firestone Country Club.

Spieth lamented his inability to find the firm fairways on the South Course following a third-round 72, but he had no issues off the tee Sunday. Spieth hit 10 of 14 fairways – four more than he had hit in any other round this week.

“I didn’t miss a fairway with my driver today,” Spieth said. “If I did, it’s because it landed in the correct part and then it funneled off into the rough. That’s really nice out on this golf course. If you can hit your driver and not miss a shot with your driver, you should definitely shoot under par out…