Dominic Stricker was the first to cause a major upset at the US Open when he knocked out seventh seed Stefanos Tsitsipas.
The original teenage star Coco Gauff knocked 16-year-old newcomer Mirra Andreeva out of the US Open on Wednesday night.
Playing in her 24th US Open, Venus Williams' 2023 campaign was brought to an abrupt end inside Arthur Ashe Stadium on Tuesday night.
Defending US Open champion Carlos Alcaraz got an easy ride into the second round at Flushing Meadows on Tuesday.
Novak Djokovic secured a return to the world number one spot with a near flawless late-night performance at the US Open.
Coco Gauff battled from a set down under the lights as the US Open served up a thriller on opening night.