South Africa's Tim Clark and Rory Sabbatini finished alone in third at 28-under-par 188. The top-seeded American team of Phil Mickelson and David Toms were one shot further back after a sizzling 15-under 57 at Vista Vallarta Golf Club's Nicklaus Course.
'We were quite a ways back heading into today, and we needed to have a good day to make up some ground,' said Mickelson, who took advantage of Saturday's better ball format. 'I think we made up half or so of the seven shots we were after.'
Mickelson and Toms jumped out of the gate with birdies on each of the first four holes. They added back-to-back birdies starting at the seventh and reached 20-under after Mickelson drained a 25-foot eagle putt at the par-5 10th.
'We even talked about it right after he made it because there was a scoreboard right there,' said Toms. 'Kind of like, hey, we are here, hopefully those guys started trying harder to make birdies and maybe they wouldn't make so many coming in.'
That eagle started another run by the Americans and they cruised with four consecutive birdies starting at the 11th. They added a birdie at the 16th and Mickelson dropped his tee shot inside eight feet for a birdie at the par-3 17th.
At the par-4 18th, Mickelson hit his approach to 10 feet and made the putt to complete the phenomenal round.
'It was fun. It was a great day,' said Toms. 'We got off to a good start. I think that was the difference from the first couple of days. We got off to a roaring start and we just kind of maintained that throughout the day.'
Mickelson and Toms, who played together at the Ryder Cup, have put themselves in position to bring home a 24th World Cup title for the United States.
'If we can post a score tomorrow, put something up there, at least get it going where those guys know that we are going to be there in the end, I see no reason why we can't come back and win this thing,' said Toms.
Maruyama and Izawa moved into contention with six birdies on the front side to make the turn at 22-under. They birdied 11 and 12 and took the outright lead at the following hole.
With a clear view of the green at the par-four 13th, Izawa holed out from the fairway for an eagle. Izawa then hit his second shot to 12 feet for birdie at the 14th and Maruyama carried the momentum onto the following hole with a birdie of his own to move to minus-29.
'We had a very good first nine holes, with six birdies, and then the turning point was probably the 13th hole, when Izawa made eagle,' said Maruyama. 'That was the shot of the day. Afterward, my play was getting better and so overall, it was a very enjoyable round.'
Izawa hit his approach within 14 feet at the last but his partner did him one better. Maruyama knocked his second shot to four feet and ran home the putt to grant Japan the 54-hole lead.
'We are not really surprised with the score, with the conditions and everything,' said Maruyama. 'We discussed this, and maybe it's not an every day score, but to play the golf, we are aiming for a good score.'
Overnight leaders Singh and Chand birdied six of the first 10 holes and picked up back-to-back birdies starting at the 12th to move to 27-under. They birdied 16 and Chand recovered from an errant drive with a birdie at the last to put his team alone in second place.
'Tomorrow is a very difficult format,' Singh said of the final-round foursomes. 'Anything is possible tomorrow, and even guys way back, five or six shots, can come up and win. So we just have to play our own game and not worry about the rest.'
England's Justin Rose and Paul Casey had five birdies and an eagle on the front nine to make the turn at 23-under. They collected three more birdies on the back side to finish four strokes off the lead at 26-under-par 190. They were joined the Canadian tandem of Mike Weir and Ian Leggatt and Scotland's Paul Lawrie and Alastair Forsyth in a tie for fifth.
The Australian duo of Adam Scott and Craig Parry shot a 7-under 65 to finish two shots further back at 24-under-par 192 along with Korea's K.J. Choi and S.K. Ho.
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