Andy Murray made a spectacular return to grand slam singles when he came from two sets down to beat Japanese world number 49 Yoshihito Nishioka.
Johanna Konta won the battle of the Brits against Heather Watson and Dan Evans also cruised through, ensuring four British men would reach round two of the US Open for the first time since 1974.
Serena Williams continued her quest for a record-equalling 24th grand slam singles title with a straight sets win over American compatriot Kristie Ahn.
Here, the PA news agency looks back at day two at the US Open.
Picture of the day
Stat of the day
Murray has now won 10 singles matches after coming from two sets behind. He is now level with Roger Federer on the most for an active player.
Point of the day
Sumit Nagal on his way to becoming the first Indian in seven years to win a singles match at a grand slam
Quote of the day
Beard of the day
Marin Cilic sported a "lucky beard" when he won the US Open title in 2014 – a similar beard was in evidence as he fought from two sets down to dispatch Denis Kudla.
Fallen seeds
Men: Guido Pella (29);
Women: Shuai Zhang (25); Veronika Kudermetova (29)
Up next:
Kyle Edmund takes on world number one Novak Djokovic while Cam Norrie looks to repeat his first round heroics against Federico Coria. Former champion Naomi Osaka is back in action against Italy's Camila Giorgi.
