MEMPHIS, Tenn. (AP) No. 5 seed Denis Kudla moved into the second round of the Memphis Open with a 6-4, 6-2 victory over Rajeev Ram on Monday.

Kudla, seeded in an ATP World Tour event for the first time, broke Ram's serve to open the second set. The 23-year-old American finished with five aces and did not face a break point.

Kudla, who was born in Ukraine, had a breakout year in 2015. He reached the fourth round at Wimbledon and advanced to the semifinals of Atlanta, a 250 Tour-level event like Memphis.

''It's great being seeded,'' Kudla said. ''You don't have to play people like Kei Nishikori in the first round.''

Nishikori, the top seed and three-time defending champion, received a first-round bye and won't play his opening match until Wednesday. He is ranked seventh in the world and is attempting to become the first four-time winner in Memphis since Jimmy Connors in the late 1970s and early 1980s.

Steve Johnson is the No. 2 seed, Donald Young is No. 3 and Sam Querrey, a former Memphis champion, is No. 4.

In a battle of qualifiers, Japan's Yoshihito Nishioka beat American Jared Donaldson, 6-3, 6-4. Nishioka, 20, is a rising player in his country who was ranked a career-best 116th earlier this year.

Also advancing into the second round were Mikhail Kukushkin, a 6-4, 7-6 (1) winner over Luca Vanni of Italy and Ilya Marchenko, who defeated sixth-seeded Sam Groth of Australia, 7-6 (4), 7-6 (2).