MILAN (AP)Jiří Lehečka earned the biggest win of his season when he beat Dominic Stricker on Friday to reach the final of the Next Gen ATP Finals.

The fifth-seeded Lehečka was dominant from the outset as he eased to a 4-1, 4-3 (4), 2-4, 4-1 victory in 82 minutes.

The Czech will face fourth-seeded Brandon Nakashima of the United States or third-seeded Jack Draper of Britain in the final of the year-ending tournament for 21-and-under players on Saturday.

After dropping the third set, Lehečka broke Stricker in the opening game of the fourth and never looked back, sealing the match when Stricker hit a return wide.

It was Stricker’s first defeat after winning all three of his group matches. Nakashima also advanced to the semifinals with a 3-0 record, including a straight-sets victory over Lehečka.

This is the fifth edition of the event, which features shorter sets of first-to-four games and other experimental format changes. New rules include no changeovers after the first game of each set and only one sit-down per set after three games; a 15-second serve clock after aces, double-faults and unreturned serves; and coaching during an opponent’s medical timeout or toilet break.

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