In a sudden transformation, Troicki started going for his shots, hitting winner after winner as he reeled off five straight games and dominated the tiebreak to even the match at a set apiece.
A short break between sets seemed to help Bautista Agut, who steadied the ship and served strongly in the final set to move within sight of his fourth title of the year.
"I was a bit tight when trying to close out the match," Bautista Agut told reporters. "It's a normal thing, though. Everyone is a bit nervous when trying to win the match.
"I was very disappointed to lose the second set after leading 5-0. But the good thing is that I was able to recover and set aside the bad feelings in the third set. I work hard on the mental side of my game and I think it is one of my strengths."
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Troicki, though disappointed to lose, took heart from his comeback.
"I'm disappointed in the loss but still proud of how I fought," he said.
In the evening semi-final, Carreno Busta took down John Millman 6-4 7-6 (5).
The 49th ranked player in the world, Carreno Busta has yet to lose a set in this tournament.
(Writing by Andrew Both in Cary, North Carolina and Jahmal Corner in Los Angeles; editing by Amlan Chakraborty)
