Acapulco - Kevin Anderson came back to defeat Alexandr Dolgopolov of Ukraine 6-1, 5-7, 6-4 on Friday and advance to the Mexican Open.
The fifth seeded South African, runner up last week at Delray Beach, will be playing in back to back finals for the first time in his career. Ranked 21st, Anderson will face the winner of the other semifinal between Andy Murray and Bulgaria's Grigor Dimitrov.
Dolgopolov lost to Rafael Nadal in the Rio de Janeiro Open final last week.
Anderson downed Frenchman Stephane Robertson, American Sam Querrey en route the to Mexican Open quarterfinals, where his opponent David Ferrer with a left leg injury.
On the women's side, top-seeded Dominika Cibulkova reached for her first final since the Australian Open after Zhang Shuai retired with a right biceps injury.
Cibulkova, 13th in the WTA rankings, was leading 4-2 in the first set when her Chinese opponent decided to quit.
"This is awesome, I came to Mexico looking for a couple of victories to get back on track, and I will be playing for a title", Cibulkova said.
The Slovakian was beat by Li Na in the Australian Open final, then lost her next three matches, including a first round exit in Qatar.
Cibulkova will play the winner of the later semifinal between America's Christina McHale and Caroline Garcia of France.
Results from the Acapulco ATP and WTA tournament on Friday (x denotes seeding):
Kevin Anderson (RSA x5) bt Alexandr Dolgopolov (UKR) 6-1, 5-7, 6-4
Grigor Dimitrov (BUL) bt Andy Murray (GBR) 4-6, 7-6 (7/5), 7-6 (7/3)
Dominika Cibulkova (SVK x1) bt Zhang Shuai (CHN x8) 4-2 - retired
Christina McHale (USA) bt Caroline Garcia (FRA) 3-6, 6-2, 7-5