Top seed Novak Djokovic says he is playing some of the best tennis of his career as he prepares to start his bid for an 18th Grand Slam at the US Open.
The Serb faces Bosnian Damir Dzumhur in the first night session on Arthur Ashe Stadium (00:00 BST on Tuesday).
Czech Karolina Pliskova, the women's top seed, faces Ukraine's Anhelina Kalinina on Ashe when the tournament begins at 17:00 on Monday.
Britain's Cameron Norrie and Kyle Edmund also play on the opening day.
Norrie, ranked 77th, has been given a tough draw against Argentine ninth seed Diego Schwartzman and plays first on court five at 16:00.