RIYADH — Ukraine’s Oleksandr Usyk retained his WBA (Super), WBO and WBC world heavyweight titles by unanimous decision against Britain’s Tyson Fury after an enthralling clash at the Kingdom Arena on Saturday. Giving up advantages in height, weight and reach to his much bigger opponent, Usyk fought superbly throughout to win 116-112 on all three judges’ scorecards as he again defeated Fury after his success in May made him the undisputed champion....