Roger Federer will have his fitness tested as he and Rafael Nadal feature on day four of the US Open in New York.
Federer's build-up to the tournament was disrupted by a back injury, and he was taken to five sets in his opening match by teenager Frances Tiafoe.
He will face Mikhail Youzhny in round two on Thursday from about 19:30 BST, before Nadal plays Japan's Taro Daniel in the second night session match.
Top women's seed Karolina Pliskova is also in action on Arthur Ashe Stadium.
She takes on American Nicole Gibbs after Ukraine's Elina Svitolina opens play on the main court at Flushing Meadows against Evgeniya Rodina of Russia.