Professional mixed martial artist Jon Jones has officially retired from the UFC and relinquished his heavyweight title to Tom Aspinall, who had held the interim belt for 18 months.

Jones, widely regarded as one of the greatest fighters of all time, has been involved in a prolonged standoff for the past year with UFC heavyweight interim

UFC President Dana White said Saturday that Jon Jones, the UFC heavyweight champ and former light heavyweight champion, has retired. Tom Aspinall, the former interim champ, is now the UFC's heavyweight champion, White said.