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.


100 horses to compete in 30th Dubai World Cup
Tiger Woods out on bail after arrest on suspicion of DUI
Iranian players hold schoolbags in protest over slain girls
Barcelona's Raphinha to miss Champions League quarters due to injury
Germany earn comeback win over Switzerland as Dutch beat Norway
