DELRAY BEACH: Second-seeded Ivo Karlovic of Croatia powered past Philipp Petzschner 6-3, 7-6 (7/3), to reach the second round of the Delray Beach International Tennis Championships.

Karlovic fired 19 aces and saved both of the break points he faced against the German on Tuesday.

After top-seeded German Tommy Haas crashed out on Monday, Tuesday saw a string of seeds move safely into the second round, along with unseeded defending champion Mardy Fish.

Third-seeded German Benjamin Becker advanced, a 6-3, 1-6, 6-0 winner over Japan's Kei Nishikori - who won this title in 2008.

"I just tried to stay calm after I got down in the second set, and refocused for the third set," Becker said. "I think I did well. I came out right after the changeover in the third set and I felt good. I was a little bit more aggressive, attacked the ball, and it helped me at the end."

Nishikori, 20, received a wild card into the tournament, his first since undergoing elbow surgery in August, an operation that followed a stress fracture in his right elbow last March.

Fish advanced when Belgian Christophe Rochus retired at 3-3 in the third set with a back injury.

Fish served up 25 aces against Rochus as he rallied to take the score to 5-7, 6-3 after two sets.

Fourth-seeded Jeremy Chardy of France advanced with a 6-3, 7-6 (7/5) victory over former two-time champion Xavier Malisse of Belgium.

Sixth-seeded German Florian Mayer beat Australian qualifier Nick Lindahl 6-4, 6-1.

Seventh-seeded James Blake had fellow American Taylor Dent in his sights, but rain stopped play in their match with Blake leading 6-1, 3-6, 5-3.

The two played until after midnight, and the match was to resume Wednesday.