The Internationals will take a 10-8 lead into the Sunday singles. It is the first time since 2003 that the Internationals have held the lead heading into the singles and, interestingly, neither team has come back to win the Presidents Cup after trailing into the singles matches. When the Internationals led in 2003, the Cup ended in a tie.   

On Saturday afternoon, Team USA finally won a session to reduce a four-point deficit to just two, but they could easily have levelled the matches after leading all four afternoon foursomes matches well into the back nine. The final match saw Byeong Hun An and Joaquin Niemann hold on to square their match with Matt Kuchar and Tony Finau having never led at any stage in the match.

But the biggest shock came with the "unacceptable" collapse from American superstars Justin Thomas and Rickie Fowler, which left golf fans gobsmacked and the Internationals in sight of a shock first triumph since 1998.

Thomas and Fowler squandered a five-hole advantage with eight to play to square their foursomes match with Marc Leishman and Abraham Ancer – the 2018 Australian Open Champion from Mexico, who remains unbeaten in his Cup debut.

Rickie Fowler sets up for his escape from the trees on the final hole. PHOTO: Getty Images.

"Speechless. It's unacceptable for us to get a half a point," Thomas said before cursing himself, especially for hooking his drive on the 18th into ti tree, from which Fowler could only punch a recovery back out on to the fairway.

"They made a couple of long putts there on 15 and 16 to keep it going (but) we had our chances and, I mean (being) flat honest, I just didn't execute. I'm just disappointed in myself for burning that, I felt like, for us on 18."

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The priceless half point ensures the Internationals will carry the lead into Sunday's deciding singles for the first time since last winning the Cup 21 years ago, also at Royal Melbourne.

The Internationals' 10-8 advantage leaves the heavily favoured and star-studded US outfit needing at least 7.5 points from the remaining 12 up for grabs to win the Cup for the eighth time in a row.

After seeing his team lose the morning fourball session 2.5 to 1.5 to trail 9-5 overall, US playing captain Tiger Woods was questioned for not picking himself in the foursomes.

When Dustin Johnson and Gary Woodland beat Adam Scott and Louis Oosthuizen 2 & 1, and Xander Schauffele and Patrick Cantlay downed Cameron Smith and Sungjae Im by the same scoreline, Woods, though, was looking like a genius.

But suddenly, the Internationals have all the momentum after Joaquin Niemann and Byeong Hun An also charged back from 2 down with five to play to rescue half a point against Matt Kuchar and Tony Finau in the final match of the day.

"That momentum switch, that's definitely going to help," Leishman said.

"To have a lead going into Sunday, we haven't done that for a long time.

"Hopefully we can bring this energy tomorrow, play some good golf, get the crowds into it, and be nice to win."

HOW THE MATCHES PLAYED OUT

Match 15

Louis Oosthuizen & Adam Scott (Internationals)

v Dustin Johnson & Gary Woodland (US)

The Internationals led 1 up early in the match but back-to-back birdies for Johnson and Woodland swung the advantage the Americans way.

The big-hitting US duo held a 2-hole advantage standing on the 16th but proceeded to botch the hole and Scott holed a four-footer for par to cut the deficit to one hole.

But a bogey at the next from the previously unbeaten combination saw Johnson and Woodland win 2 & 1 on the back of a par and help the US team inch closer to the Internationals.

“Had a couple of lip-outs on 11 and 12 and put us 2-down,” Scott said. “They were good putts and lipped-out. We just couldn't quite get back in it unfortunately. The putts didn't drop this afternoon for us.”

Johnson said he and partner Woodland played solid.

“It was a tough match. We knew it was going to be tough at the start, but like I said, we played really solid and it's nice to get a point on the board.”

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Match 16

Marc Leishman & Abraham Ancer (Internationals)

v Justin Thomas & Rickie Fowler (US)

The Americans jumped quickly out of the blocks and won five of the first seven holes and were seemingly en route to a crushing victory over Leishman and the previously unbeaten Ancer.

But Leishman and Ancer chipped away at their lead, making birdies at the 11th and 12th holes to get back to 3-down. When the Americans bogied the 16th and 17th holes, Leishman and Ancer had the opportunity to square the match and grab a crucial half point.

Marc Leishman punches the air after making birdie. PHOTO: Getty Images.

Their task was made easier when Thomas hooked his drive into ti-tree left of the fairway, forcing Fowler to punch their second shot clear but well short of the green. In the meantime, Leishman smoothed a lovely approach to about six-feet from the hole. When Thomas’ long par-saver missed, Leishman gave the Americans their short bogey putt and the Americans did likewise for Ancer’s birdie putt. The International pair had done the unthinkable and squared the match.

“We kept believing. We told ourselves that we were going to keep going at it and we were going to fight until the end,” Ancer said. “We were not just going to give up. We've just got to find a way to get it done and we did.

“It's pretty spectacular, the emotions were great, and the people were amazing, so couldn't be more stoked.”

Match 17

Cameron Smith & Sungjae Im (Internationals)

v Xander Schauffele & Patrick Cantlay (US)

Of all the International pairings that looked likely to win their match it was Smith and Im. The duo jumped to a 3-up lead through the opening four holes but the Schauffele-Cantlay combination strung together a strong back nine to move ahead at the 13th hole.

Cameron Smith and Sungjae Im were all smiles early in their foursomes round. PHOTO: Getty Images.

When the Americans moved to 2-up through 15 holes on the back of a tap-in birdie, they closed out with two pars to claim the point 2 & 1.

“We just didn't really – we probably didn't putt as good as their guys. Every time they needed to make a putt, they made a putt,” Smith said.

Match 18

Byeong Hun An & Joaquin Niemann (Internationals)

v Matt Kuchar & Tony Finau (US)

After opening the match with a birdie to go 1-up, the American pair of Kuchar and Finau led for the next 14 holes.

An and Niemann made back-to-back birdies at the 14th and 15th to level the match but they were unable to go the next step and claim the lead over the closing trio of holes.

The International team react to Byeong Hun An's missed birdie putt on 18. PHOTO: Getty Images.

An had a chance to steal the vital last point of the session, but his birdie putt from six feet shaved the hole and the match was halved.

“That was a big half point. To be fair, we were struggling a little bit on the front nine,” An said. “We were not hitting it great. We were not in the places where we wanted to be, but you know, at the end we got a half-point.

“I'm a little disappointed I missed the putt (at the last), but still, we're in a great position going into Sunday.”