U.S. Open semifinalist Frances Tiafoe has aimed a torrent of expletives at the chair umpire after losing a match at the Shanghai Masters.

Frances Tiafoe puts his head in his hands as he leaves Arthur Ashe Stadium after losing his match against Taylor Fritz on day twelve of the U.S. Open tennis tournament at the USTA Billie Jean King National Tennis Center. Mandatory Credit: Mike Frey-Imagn Images / Mike Frey-Imagn Images

Frances Tiafoe has apologised for his foul-mouthed tirade directed at a chair umpire after the American received a time violation and then lost to Roman Safiullin in the third round of the Shanghai Masters on Tuesday.