Despite an epic battle match lasting two and a half hours, Stefanos Tsitsipas did not manage to get past his rival Reilly Opelka to reach the final of the ATP Toronto Masters.

The American two-metre-plus giant blasted 17 aces in the match ending 6-7 (2/7), 7-6 (7/4), 6-4 and stated fully aware of his winning serve throughout the tournament.

“There are no easy draws at Masters 1000s, every match is a nightmare. But I’ve got a lot of confidence going and I’ve carried it through each match. I’m putting pressure on guys with my serve and they can feel it.”

Tsitsipas was showing signs he could turn the game around in the third set until Opelka broke for a 4-3 lead.

“He prevailed, it just didn’t go my way,” Tsitsipas said. “But there is hope for next time, it’s all right.

Opelka had also ousted Greek Australian Nick Kyrgios in the first round.

Overcoming third-seeded Tsitsipas, marked Opelka’s first victory over a top-five opponent.

The American will face Russian top seed Daniil Medvedev at the Toronto final on Monday 6am (AEST).

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