MIAMI • Roger Federer described himself as "incredibly lucky" to have beaten Tomas Berdych in the Miami Open quarter-finals, but credited his 6-2, 3-6, 7-6 (8-6) win on Thursday to thinking young.
The Swiss tennis star trailed 6-4 in the third set tie-breaker but fought back and won the match when Berdych double-faulted.
"I was like, 'Wow, double fault. Are you kidding me? You're too kind, Tomas. Why? How do I deserve this one?' " Federer said.
"I don't feel like I deserved it that much, a double fault at that moment. I guess he was playing on the edge. I got incredibly lucky. Could have gone either way."
The 35-year-old was asked whether he thought experience helped him deal with the pressure of a tight tie-break decider and replied that it could be a double-edged sword.
"I guess you get better over time handling pressure," said the 18-time Major champion.
"Then you have to be careful, I think, as you grow older, not to play too conservative when it matters. You start playing percentages way too much when you get older because you've seen too many times what can happen.
"Sometimes when you have that young mind, you just go for it, and that's when actually great things do happen. You've just got to play committed tennis. So, for me, it's always a balance between playing the percentages, yet play free and sort of young in the mind."
The world No. 6 will next face Nick Kyrgios (this morning, Singapore time), after the Australian edged out teenager Alexander Zverev 6-4, 6-7 (7-9), 6-3.
Tempers flared late in their quarter-final when a botched line call and contentious decision by the chair umpire to allow a challenge on the point caused both players to react angrily.
The pivotal moment came on the first point of the sixth game in the deciding set, when a lob from Zverev sailed long.
The linesman mistakenly called the ball in and Kyrgios, despite believing it was out, decided to try a shot between his legs before challenging.
Chair umpire Fergus Murphy allowed the challenge, a decision that former player Brad Gilbert called "wrong" during television coverage, and replays showed the ball was indeed out.
The point was awarded to Kyrgios which left Zverev seething, the German arguing that the 12th seed should not have been allowed to challenge the call after hitting the ball.
Flustered, he lost the game, which turned out to be the only service break of the set, and Zverev gave Murphy a piece of his mind at the next change over.
"You might cost me the match," he said. "You know that. The decision is absolute crap."
Kyrgios, meanwhile, was not happy either, giving the linesman a verbal spray for missing the call in the first place, but settled down to hold serve and finally clinch victory on his sixth match point.
Later, Johanna Konta became the first British woman to reach a Miami Open final when she outlasted American veteran Venus Williams 6-4, 7-5 .
The 10th seed will play Caroline Wozniacki in today's final after the Danish 12th seed won her semi-final 5-7, 6-1, 6-1 against Czech second seed Karolina Pliskova.
AGENCE FRANCE-PRESSE, REUTERS
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