ST. PETERSBURG, Russia (AP) Alex Bogomolov Jr. of the United States and Marin Cilic of Croatia won three-set matches to advance to the quarterfinals of the St. Petersburg Open on Thursday.

Dmitry Tursunov of Russia was eliminated in straight sets in the second round.

Bogomolov Jr. beat Philipp Kohlschreiber of Germany 6-4, 3-6, 7-5, while fourth-seeded Cilic rallied to oust Somdev Devvarman of India 5-7, 6-1, 6-3. Tursunov lost to Potito Starace of Italy 6-2, 6-4.

In his second consecutive quarterfinal appearance in two weeks, Bogomolov Jr. will play Serbian qualifier Dusan Lajovic, who recovered to beat Israeli wildcard Dudi Sela 2-6, 6-2, 6-1.

It was a good match,'' Bogomolov Jr. said.He was playing much better by the end of the match. He received perfectly when I was serving for the match at 5-3 up and broke me. I was lucky when he double-faulted on second match point. I'm happy that I will play in the next round.''

The 53rd-ranked Starace broke Tursunov two times in the first set and in the fifth game of the second. Tursunov saved three match points at 5-4 before earning his only break point of the match, but the Italian served two winners and closed the match with a backhand volley.

``He (Starace) served well today while I rarely hit (the ball) with the center of my racket,'' Tursunov said.

The 84th-ranked Devvarman broke in the 11th game of the first set, but the 24th-ranked Cilic, who is looking for his first title this season, won five consecutive games in the second set and broke twice in the decider to advance.

Bogomolov Jr. is making his debut at a second consecutive event in Russia after reaching the quarterfinals at the Kremlin Cup last week. He said this week that he plans to represent Russia in the Davis Cup.

Kohlschreiber won three games in a row and saved a match point as he fought back from 5-2 down to tie it 5-all. But serving at 6-5 down and 30-all, the unseeded German returned wide and double-faulted on match point.