Anderson, ranked fifth, was hurt during last month's Grand Slam tournament in Australia. He was runner-up last year at Wimbledon and says his victory on Long Island "kick-started my year in 2018 and I was very excited to return."
His withdrawal leaves American John Isner as the highest-ranked player in the field at No. 9. Anderson outlasted Isner in a marathon semifinal at Wimbledon. Australian Alex de Minaur, last year's ATP top rookie, also pulled out of the tournament because of an injury.