Billy Horschel continued his fine run of form to take a two-shot lead at the halfway stage of the Valero Texas Open.
Horschel, who finished tied for second at last week's Houston Open, signed for a second successive round of 68 to break out of what had been a logjam at the top of the leaderboard.
He struggled early in his second round, with bogeys at the first and fourth, but from then on the Florida native was in imperious form, following his second dropped shot with three birdies and picking up strokes at the 17th and 18th to move two in front.
Until then, there had been a four-way tie on six-under with Charley Hoffman, Daniel Summerhays and Steven Bowditch level with Horschel at TPC San Antonio.
McIlroy on song
Hoffman performed best of that triumvirate, following his opening 71 with a fine 67, with Summerhays and Bowditch each carding three-under rounds of 69 for the second straight day.
There was also much more positive news for former world No 1 Rory McIlroy, who showed distinct signs of returning to his best in a five-under par round of 67 that lifted him into a tie for fifth place.
McIlroy, yet to finish in the top five this season, had a mixed front nine that ended one-under the card, but he finished like a train with three straight birdies to fly through the field and put himself bang in contention for the weekend.
He is in a seven-way tie on five-under alongside Brendon de Jonge, Jim Furyk, KJ Choi, Retief Goosen, Ben Kohles and veteran Lee Janzen.
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