Former US Open champion Juan Martin del Potro defeated fifth-seeded South African Kevin Anderson in straight sets on Friday to reach his third straight ATP semifinal on Friday.
Argentina's del Potro dispatched Anderson 6-4, 6-4 to book a clash with second-seeded American Mardy Fish in the semi-finals of the $442,500 ATP Delray Beach International Championships.
Fish, the 2009 winner here, eased past Colombian qualifier Alejandro Falla 6-1, 6-4.
"Three semi-finals in three weeks, so it's great for my comeback," said Del Potro, who reached the final four in San Jose and Memphis over the past two weeks. "I hope I play well tomorrow against Mardy."
Del Potro, the 2009 US Open champion, is on the comeback trail after a wrist injury and surgery derailed his 2010 season.
He edged Anderson, ranked 40th in the world, by converting both of his two break points while never offering the South African a break opportunity.
Saturday's other semi-final will feature Japan's Kei Nishikori, the 2008 champion, against sixth-seeded Janko Tipsarevic of Serbia.
Nishikori, whose only ATP singles crown came at Delray Beach, rallied to defeat US qualifier Ryan Sweeting 6-7 (5/7), 6-2, 6-4.
Tipsarevic defeated Croatian Ivan Dodig 7-6, (7/0), 6-1.
Sweeting, ranked 118th and in his first career ATP quarter-final, saved two break points in the first set and broke a 4-4 tie-breaker deadlock by winning three of the next four points to claim the first set in 49 minutes.
Nishikori, ranked 66th, broke Sweeting to open the second set and denied Sweeting on his only three break-point chances of the match to force a third set, in which he managed the lone break to win after two hours, 10 minutes.
"I'm really happy to be in the semis on Sunday. It's my favorite tournament, so hopefully I can go farther," said Nishikori, who lives in Florida in part to escape the spotlight back home in Japan.
"No one knows me here, so it's much easier for me," he said. "If I stayed in Japan all the time, I might go crazy. I have to wear sunglasses and a hat, but it's fun sometimes when everybody knows me. It's good to be me."
Tipsarevic, ranked 52nd, is seeking his first ATP title after having lost finals at Moscow in 2009 and s-Hertogenbosch last year. His most recent ATP semi-final was last month in Chennai.