Memphis, TN, USA, 11 February 2015 | AFP

Bernard Tomic has set up a second-round showdown with Ukrainian fourth seed Alexandr Dolgopolov, after a hard-fought win at the ATP Memphis Open.

The 22-year-old Australian rallied after a scratchy first set on Tuesday to oust Dutchman Igor Sijsling 4-6 6-3 6-2.

The world No.49 surrendered two service breaks in the opening set but saved 5-of-6 break points over the final two sets while breaking four times, three in the final set.

Sam Groth also advanced, the big-serving Aussie took just over an hour to defeat Taiwan’s Yen-Hsun Lu in straight sets.

Groth dropped just three points on his booming first serve to win 6-4 6-3.

Groth will take on South African second seed Kevin Anderson, who like Tomic’s opponent Dolgopolov received a first-round bye.

While it was a good day for those two it was less so for 18-year-old whiz-kid Thanasi Kokkinakis, who fell 6-3 6-4 to fellow qualifier Denis Kudla from the United States.

Also booking a spot in the round of 16 was Croatian fifth seed Ivo Karlovic who blasted 23 aces in his defeat of Slovakian Lukas Lacko 7-6(7) 6-3.

Karlovic, ranked 25th, had won their only prior meeting in the first round at Wimbledon in 2009.

The big-serving 35-year-old will next face US qualifier Austin Krajicek.