Steve Stricker birdied and won the final two holes against Scott Piercy this morning to move into this afternoon's quarterfinals. Stricker beat Piercy 1 up.
Stricker will face 2010 Match Play champion Ian Poulter in the quarters. Poulter topped Tim Clark 5 and 3.
Meanwhile, defending champion Hunter Mahan won his ninth straight match at The Golf Club at Dove Mountain, rolling over German Martin Kaymer 5 and 4. Mahan has won 11 of his last 12 matches in Southern Arizona.
Other winners included American Matt Kuchar, who topped Belgium's Nicolas Colsaerts 4 and 3. He'll face Robert Garrigus, who beat Fredrik Jacobson 3 and 1.
Bubba Watson, the only top 10 seed remaining, lost to Jason Day 4 and 2. Day will face Graeme McDowell in the quarters.
The quarterfinals round began at 12:20 p.m.