Kevin Na secured a one-shot lead with a brilliant, blemish-free round of eight-under 62 on day one of the Fort Worth Invitational in Texas.
Fort Worth Invitational
The American hit a trio of birdies before the turn and holed the ninth with a superb chip, earning cheers of approval from the crowd as he knocked Charley Hoffman off the top of the leaderboard at Colonial Country Club.
Compatriot Hoffman had temporarily taken first place with a bogey-free round that saw seven birdies, with none of his par putts from more than five feet.
Lurking a shot behind Hoffman are Argentine Emiliano Grillo, Venezuelan Jhonattan Vegas and Americans Andrew Putnam and Beau Hossler on six-under.
Englishman Justin Rose was four shots off the lead and tied eighth after carding a near-spotless round of 66 that saw back-to-back birdies on holes 11, 12 and 13.
His first time at Fort Worth since 2010, Rose failed to finish in the top 10 in four previous appearances.
The US Open winner was considerably ahead of the next Briton, Scotsman Russell Knox who went round one-under to tie 44th, while countryman Martin Laird hit a level par 70 that saw five birdies wiped out by five bogeys, leaving him tied in 61st.
The shot of the day went to Satoshi Kodaira of Japan, who hit an albatross on the first.
But he ended the day with a double-bogey on the ninth, leaving him alongside Rose on four-under.
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May 25, 2018, 6:00pm
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Featured groups coverage from the Fort Worth Invitational continues from 6pm on Friday, live on Sky Sports Golf