Second seed Rafael Nadal will continue his bid for a fourth U.S. Open title on Monday when he takes on Croatia's Marin Cilic at the Arthur Ashe Stadium.
The Spaniard is yet to be tested at this year's tournament at the Billie Jean King National Tennis Center in New York and has also been boosted by the exit of defending champion and top seed Novak Djokovic.
Cilic has been taken to four sets by both Cedrik-Marcel Stebe and John Isner, but the 2014 champion knows exactly what it takes to win the title in New York.
In the women's draw, American qualifier Taylor Townsend and 15th seed Bianca Andreescu are also in action on Monday night.
Townsend has already caused a stir at the U.S. Open by knocking out 2019 Wimbledon champion and fourth seed Simona Halep in the second round.
She now goes up against one of the most in-form players on the WTA Tour. Andreescu has won her last 10 matches and saw off former world No.1 Caroline Wozniacki to book her place in the fourth round.
Monday Night Schedule
Arthur Ashe Stadium - 7 p.m. (ET)
(22) Marin Cilic vs. (2) Rafael Nadal
Taylor Townsend vs. (15) Bianca Andreescu
TV Info: ESPN (U.S.)
Nadal is the new favourite to win the final Grand Slam of 2019 after Djokovic was forced to retire from his clash against Stanislas Wawrinka due to a shoulder injury:
The second seed has been in superb form throughout the year at the top events in the tennis calendar and will hope to continue that run in New York and clinch a 19th Grand Slam.
He reached the final of the Australian Open, won the French Open for the 12th time and was knocked out of Wimbledon in the semi-finals by Roger Federer after another memorable battle between the two former champions:
Nadal will be expected to progress past Cilic and reach the quarter-finals. He has won six of the eight meetings between the two players going into the clash.
The U.S. Open showed how the two players match up ahead of the encounter:
The 33-year-old should also be in good shape going into the second week. He has yet to drop serve or a set in his wins over John Millman and Hyeon Chung. Nadal was also handed a walkover in the second round when Thanasi Kokkinakis withdrew because of a shoulder injury.
Cilic has not been as convincing in 2019 or at the U.S. Open. His was knocked out in the second round of both Wimbledon and the French Open but did make it to the fourth round in Australia.
The Croatian has already acknowledged how difficult his task will be against Nadal on Monday, per the ATP Tour.
"I'm going to have to create chances with Rafa. He's definitely having a great season and playing really well," he said. "We played quite a few times already. We know each other really well. I'm going to have to be ready for a tough battle."
Cilic's last win over Nadal came at the Australian Open in 2018 when the Spaniard withdrew through injury while trailing in the fifth set. The 30-year-old's only other win over Nadal was in 2009 at the China Open in Beijing.
Meanwhile, Townsend and Andreescu will meet for the first time at the Arthur Ashe Stadium for a place in the quarter-finals. Both players are in the fourth round of a Grand Slam for the first time in their careers.
Townsend can expect plenty of support from the home crowd and has spoken about the confidence she has gained from her wins over Halep, Kateryna Kozlova and Sorana Cirstea:
The American's ability to serve and volley has already thrilled supporters in New York and will prove a real test for Andreescu.
WTA Insider showed how effective her style was against Halep:
Yet 20-year-old Andreescu has been in tremendous form in 2019, picking up wins in Toronto and Indians Wells.
She is playing at Flushing Meadows for the first time but is yet to drop a set in wins over Katie Volynets, Kirsten Flipkens and Wozniacki.
Journalist Jose Morgado highlighted her current run of form:
As the seeded player, Andreescu will be expected to prevail and should have the versatility to cope with Townsend fearless style of play, but the 23-year-old's victory over Halep shows she is capable of pulling off an upset.