MILAN (AP)American Brandon Nakashima stayed perfect in Milan as he won the Next Gen ATP Finals on Saturday with his second straight-set victory over Jiří Lehečka this week.

Nakashima took just 80 minutes to win 4-3 (5), 4-3 (6), 4-2, securing the title on the first of three championship points when Lehečka sent a forehand long.

The fourth-seeded Nakashima won all five of his matches at the year-ending tournament for 21-and-under players, including a straight-set victory over Lehečka in the group stage.

Lehečka was out for revenge as well as the title and broke Nakashima’s serve in the very first game. But Nakashima broke back in the sixth game to take the set to a tiebreaker, where the American raced into a 5-0 lead and went on to take the set.

Lehečka threatened to start the second set in similar fashion but Nakashima managed to save two break points early on.

Indeed the next break of serve was to prove the most important as it came in the final game of the tournament.

It was Nakashima’s second appearance at the Next Gen Finals, having lost to compatriot Sebastian Korda in the semifinals last year.

Nakashima won his first ATP title in his home city of San Diego in September.

This is the fifth edition of the Next Gen ATP Finals, which has featured shorter sets of first-to-four games and other experimental format changes. New rules included 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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