Day two at Dubai Tennis stadium saw Sinner, Hurkacz and Khachanov progress to the next round.
At the Dubai Duty Free Tennis Championships, fourth seeded Italian Jannik Sinner has beaten Spain's Alejandro Davidovich Fokina on centre court in three sets.
On court one, fifth seed Hubert Hurkacz won against Kazakhstan's Alexander Bublik 6-3 6-1.
In the day's early matches, American Mackenzie McDonald defeated seventh-seeded Russian Aslan Karatsev 7-5 6-3 on Centre Court.
Russia's Karen Khachanov beat Alex de Minaur from Australia on Court one 6-3 6-7 7-5.
Dubai Capitals overpower Abu Dhabi Knight Riders by 83 runs
Mid East finished strong with victory against Arabia
Norris takes F1 title as Verstappen wins Abu Dhabi race
Neser fires Australia to eight-wicket win in second Ashes test
Denmark's Neergaard-Petersen holds nerve to claim Australian Open title
