Matt Kuchar turned three up on Jason Day as the American closed in on a place in the WGC-Accenture Match Play Championship final in Tucson.
Australian Day failed to make a birdie on the front nine and his American opponent, playing in the last four for the second time in three years, took full control with a steady rather than spectacular showing at Dove Mountain.
Having gone one down with a bogey at the long second, Kuchar leveled when he won the fourth with a par.
The Ryder Cup star went one up with a birdie at the short sixth, and looked like going two in front when Day hit his drive on the seventh into the desert.
The 25 year old pulled off a remarkable recovery – firing his second to the edge of the green, and getting away with failing to get up-and-down when Kuchar three-putted.
Day’s luck ran out at the long eighth, as Kuchar’s second birdie of the day put him two up, and a par at the ninth was enough to go three clear as his opponent struggled to find the form that got him past Major Champions Bubba Watson and Graeme McDowell on Saturday.