The action is already heating up in both Doha and Dubai this week, as the world's top names made it past tricky competitors in their opening rounds.
These are the Top 5 Photos from Monday. (All photos Getty Images.)
Roberto Bautista Agut
After a tough first-round loss in Rotterdam, the Spaniard looked to be headed in a similar direction against American Reilly Opelka in his Doha opener. However, the 32-year-old flipped the switch in the second set to push the affair to a deciding set, and ultimately prevailed with a 4-6, 6-3, 6-4 victory.
Bautista Agut will next face Alexander Bublik for a spot in the 500-level event's quarterfinal.