Bulgaria's Grigor Dimitrov, the No. 4 seed, defeated fifth-seeded South African Kevin Anderson 7-6 (7-1), 3-6, 7-6 (7-5) in the final of the Abierto Mexicano Telcel in Acapulco, Mexico.
The victory early Sunday gave Dimitrov, the world No. 22, his first ATP 500 title and second career title.
"Belief is the only thing that kept me going today," Dimitrov said.
The 22-year-old Bulgarian stunned Andy Murray in the semifinals, rallying from a set down to grind out a 4-6, 7-6 (7-5), 7-6 (7-3) victory in a match that ended at 2:30 a.m. Saturday.
"I didn't think I was going to come back after last night's match. I'm really happy. This title means a lot to me," Dimitrov said.
Dimitrov, whose ranking will rise from No. 28 to a projected career high of No. 16, took home a check for $316,400.
In the women's event in this Pacific resort city, top seed Dominika Cibulkova of Slovakia beat unseeded American Christina McHale 7-6 (7-3), 4-6, 6-4.
The 24-year-old Cibulkova, the Australian Open finalist, won her fourth career title, while the 21-year-old McHale made her first WTA Tour final.
Cibulkova took home $43,000 in prize money and 280 ranking points, while McHale won $21,400 and earned 180 WTA ranking points. EFE