US second seed John Isner rallied Friday to reach the ATP Delray Beach Open semi-finals, where he will try to deny Marin Cilic his third final in as many weeks.
Big-serving Isner fired 18 aces in outlasting US qualifier Rhyne Williams 4-6, 6-3, 6-2 while Cilic, a seventh seed from Croatia, dispatched Russia's Teymuraz Gabashvili 6-2, 6-3.
Cilic won his fourth career ATP crown on home soil at Zagreb two weeks ago and last week reached the Rotterdam final, losing to Czech Tomas Berdych.
Hitting 12 aces and converting five of six break points, Cilic advanced in 79 minutes and took the 2014 lead in match wins with 16.
"Good times are rolling. It's pretty good," Cilic said. "This is my first time ever (reaching) two finals in a row, and a semi-final, so that's huge for me. It's very positive."
The other semi-final will send South African fourth seed Kevin Anderson -- who eliminated Australian Marinko Matosevic 6-7 (3/7), 6-3, 6-3 -- against 142nd-ranked US qualifier Steve Johnson, who eliminated Spanish sixth seed Feliciano Lopez 6-3, 6-2.
Anderson improved to 3-0 lifetime against Matosevic by winning a rematch of their 2012 Delray Beach final.
"I've played him a couple times before and it's a battle each time," Anderson said. "I just hung in there and finally got that breakthrough in the second set. It was gusty and it was tough to get a rhythm.
"I'm in the semis and that's a great feeling."
Anderson, who fired 10 aces and connected on 61 percent of his first serves, won his only other ATP title in 2011 on home soil at Johannesburg.
Johnson, who upset top seed Tommy Haas in the second round, has reached his first ATP semi-final. He has already beaten Anderson this year, ousting him at Auckland last month.
"He's going to have the experience out there, but I played him tough earlier this year," Johnson said. "It's going to be a comfortable match for me because I've practiced with Kevin. I'm hoping to go out there and just be confident and ready to go."