(Photo credit: Aaron Doster-Imagn Images)

In the third and final set of his Cincinnati Open quarterfinal match against Andrey Rublev on Friday afternoon, Carlos Alcaraz committed 15 unforced errors and authored three double faults.

And, yet, the second-seeded Spaniard found a way to claim a 6-3, 4-6, 7-5 victory over the ninth-seeded Russian in Mason, Ohio.

'I maintained positive thoughts all the time, even though I lost focus a few times during the second set,' Alcaraz said. 'Playing someone like Andrey, when you lose focus on two or three points, it (can) cost you the set or almost the match. I just stayed strong mentally and that's what I'm most proud of.'

Alcaraz squandered a 5-3 lead in the third set, but then he held his serve and then broke Rublev for the fourth time to set up Saturday's semifinal against either No. 3 Alexander Zverev of Germany or No. 5 Ben Shelton. The Zverev-Shelton quarterfinal match starts at 7 p.m. ET.

Alcarez prevailed, in part, because Rublev made even more miscues in the third set. He racked up five double faults and 17 unforced errors in the third after committing just three double faults and 17 unforced errors in the first two sets combined. That included a double fault on match point that had Alcaraz pumping his fist over his 15th straight victory in an ATP Masters 1000 event.

'It's just (about) accepting the moment, accepting that I am playing a third set, accepting that it's going to be a really tough battle, and I love that,' Alcaraz said. 'It was extreme conditions, but I just love playing in front of this energy. I am just really happy to live these kinds of experiences, so I just remind myself of that in these moments.'

--Field Level Media