Updated

Defending champion Hunter Mahan cruised past Martin Kaymer, 5 & 4, to advance to the quarterfinals at the World Golf Championship - Accenture Match Play Championship.

Mahan, the sixth seed in the Gary Player Bracket, won five of seven on from the 11th to the 17th as they started on the back nine. Mahan was 5-up on the 2011 runner-up before Kaymer birdied the second to get within 4-down, but Mahan birdied the fourth at The Golf Club at Dove Mountain to regain his 5-up lead and the match was over one hole later when they halved the fifth with pars.

The reigning champ will take on U.S. Open champion Webb Simpson, who held off Gonzalo Fernandez-Castano, 2-up. Simpson won the first with a birdie, then they traded the fourth and fifth holes. Simpson took the sixth and seventh. He birdied the 11th to go 4-up, but the Spaniard won the 12th, 14th and 17th to inch within 1-down.

At the ninth, their last, Fernandez-Castano 3-putted for bogey and conceded Simpson's par putt and the match.

The Bobby Jones Bracket will have Graeme McDowell facing Jason Day. McDowell took down Shane Lowry, 3 & 2. Day handled Masters champ Bubba Watson, 4 & 3.

Lowry birdied the second to go 1-up, but McDowell won five of the next seven holes to jump 4-up. After five straight halves, Lowry took the 15th with a par. They both parred No. 16 to give McDowell the match.

Day, the 11th seed, never trailed against Watson. Day won the first, fourth and sixth, while Watson took the second and seventh. The Australian birdied the eighth and parred the ninth to make the turn with a 3-up lead. They traded wins at 11 and 12, before Watson conceded the hole and the match at No. 15.

The Ben Hogan Bracket will have sixth-seeded Matt Kuchar facing ninth-seeded Robert Garrigus in the quarters. After Kuchar and Nicolas Colsaerts traded wins at one and two, Kuchar won back-to-back holes from the third and seventh to go 4-up.

Colsaerts got one back at the ninth, but after five halves in a row, Kuchar closed out the 4 & 3 win with a par on the 15th.

Garrigus led Fredrik Jacobson 3-up at the turn, but Jacobson won three in a row from the 11th to square the match. Garrigus responded with three wins in the next four holes to earn the 3 & 1 win.

Two former champions will face each other in the Sam Snead Bracket. Ian Poulter, the 2010 champ, will take on 2001 winner Steve Stricker in the quarterfinals. Their third-round matches both started on the back nine.

Poulter won three in a row from the 16th to go 3-up. He took the third with a par and a birdie at the sixth gave Poulter the 5 & 3 victory.

Stricker, who is celebrating his 46th birthday, took down Scott Piercy in a fierce match. Piercy took the lead three times, and all three times Stricker rallied to square the match. Stricker birdied the eighth to even things up. At the ninth, their last, Stricker ran home a 31-footer for birdie and the 1-up victory.

NOTES: Every winner on the PGA Tour this year has been American, and there are four Americans in the quarterfinals, but two -- Kuchar and Garrigus -- are facing each other ... The matches in the Player and Snead Brackets started on No. 10 as they tried to save time in order to get the third round and quarterfinals both done on Saturday ... The start of the third round was delayed 45 minutes by frost.