Ben Curtis holds a three-shot lead going into the final round of the Valero Texas Open, despite carding a one-over 73 at TPC San Antonio.
The 34-year-old American picked up a pair of double bogeys in treacherous conditions but still extended his overnight lead by a single stroke as his nearest rivals were unable to capitalise.
His closest challenger and playing partner David Mathis imploded with a five-over 77, to leave Matt Every in second place on six under.
Curtis had been flawless through the opening two days, but he took six to double bogey the first, while he carded a seven at the par-five eighth to go out in 39.
The former Open Championship winner responded with three birdies and a bogey after the turn which proved enough to extend his lead at nine-under.
John Huh had an equal-best round of five-under 67 to leave him tied for third on four under with South Korean duo Charlie Wi and Noh Seung-yul, while Matt Kuchar is among a group of five on three under.
