David and Goliath, meet Kevin Anderson and Rafael Nadal.
Nadal, the top-ranked men's tennis player in the world, will take on Anderson, the lowest-seeded men's finalist at the US Open since the ATP's computer rankings began in 1973, for all the marbles on Sunday either at or after 4 p.m. ET.
Nadal took control of the semifinal with his nasty forehand to end Juan Martin del Potro's Cinderella run in the semifinals on Friday. That same day, Anderson, the 31-year-old South African, poked his way past Pablo Carreno Busta and into the first Grand Slam final of his decade-long pro career.
Here's a preview and prediction for the finale in Flushing Meadows.
Nadal is aiming to turn his third major final of 2017 into his second Grand Slam championship this year. The 31-year-old lost to Roger Federer in the Australian Open final before storming to his record-extending 10th French Open crown.
"It's been an amazing season, of course, after a couple of years with some troubles, injuries, tough moments," Nadal said, per the Associated Press. "So this year, since the beginning, has been a very emotional year."
Nadal's semifinal win over Del Potro marked his 15th straight victory in that round of a Grand Slam tournament. His last loss under those circumstances? At the 2009 US Open, to Del Potro.
The Spaniard's speed and power has been on full display over the last two weeks at the USTA Billie Jean King National Tennis Center. He figures to be a handful for Anderson, who isn't exactly fleet of foot.
Anderson's potential advantage? A massive serve, courtesy of his 6'8" frame.
Win or lose, he's already made history. He's the first South African to play in the US Open final since the start of the Open era and stands as the lowest seed ever to get this far in the event.
He celebrated accordingly on Friday. After overcoming Carreno Busta in four sets to advance past the semifinals, Anderson scaled his way to his guest box in the stands.
Another victory would make Anderson, who won a national doubles championship at the University of Illinois at Urbana-Champaign, the first former collegiate player to win a men's singles Grand Slam since John McEnroe (Stanford) claimed his last US Open win in 1984.
If past experience is at all predictive of future success, Nadal should make fairly quick work of Anderson on Sunday afternoon.
For one, he's 4-0 in previous matches against his challenger from Johannesburg. What's more, Nadal has won nine of 10 sets across those meetings.
In the bigger picture, the gap between Nadal and Anderson is nothing if not astounding. The former is aiming for his third US Open trophy and 16th major title. The latter had never so much as sniffed a Grand Slam final in 33 previous tries.
Should this year's last major final end with anything but another piece of hardware in Nadal's hands, it will be one of the greatest sports upsets of 2017 so far.
Which is to say, expect Rafa to reign supreme once again in New York City, for the first time since 2013.
Predicted Result: Nadal to win in three sets.