Underdog Kevin Anderson is 11/2 with Sky Bet to clinch the US Open title with victory over hot favourite Rafael Nadal in Sunday's final.
Nadal defeated a weary Juan Martin del Potro in the early hours of Saturday morning to set up a showdown with South African Anderson.
After upsetting Roger Federer in the quarter-final, Del Potro was looking to engineer a repeat of 2009.
On that occasion he allowed Nadal just six games in the semi-finals before beating Federer over five sets to win his first, and so far only, grand slam title.
It looked a distinct possibility when he powered his way to the opening set but he could not sustain the pace and Nadal romped home to win 4-6 6-0 6-3 6-2.
Ahead of his 23rd slam final, the world number one said: "It means a lot. It's been an amazing season after a couple of years with some troubles. This year since the beginning has been very emotional.
SKY BET PRICE BOOST: Rafael Nadal to lose the 1st set and win 3-1 - 10/1
"To have the chance to be in another final here is very, very important for me. We did a lot of good work, we believed in what we were doing and I still have the passion and the love for this game."
The Spaniard is looking to win his first grand slam title away from the French Open since the second of his titles in New York in 2013 and match Federer by claiming two slams this season.
He is 1/8 with Sky Bet to do so against first-time finalist and 11/2 shot Anderson, who was the man to take advantage of the open bottom half of the draw.
The 31-year-old, who stands 6ft 8in, defeated Pablo Carreno Busta 4-6 7-5 6-3 6-4 to become the first South African player to reach a grand slam singles final since Kevin Curren made two in the mid-1980s.
Anderson said: "It's definitely an amazing feeling being in this position and I have worked very hard to get here. I have given myself a shot at being in the finals and I will be playing for a grand slam trophy.
"These grand slams are tough. We've been privileged to play with some of the best players to ever play the game and it's nice that some of them gave us a shot at this tournament."