• The 2018 U.S. Open began with a shock on Monday, with the loss of top-ranked Simona Halep in one of the first matches of the day.
• Andy Murray won his first match at Grand Slam event in more than a year, but it wasn’t easy.
• Sloane Stephens began her title defense at Armstrong Stadium with a victory over Evgeniya Rodina.
• Venus Williams played a thrilling three-setter against her fellow U.S. Open champion Svetlana Kuznetsova.
• Refresh here for live results and analysis from the first day of the 2018 U.