J. J. Wolf ousts Frances Tiafoe in Dallas Open quarters as John Isner advances

DALLAS (AP) — J.J. Wolf rallied for a three-set victory over No. 2 seed Frances Tiafoe, and John Isner won his 500th career tiebreaker in another straight-sets win in the quarterfinals of the Dallas Open on Friday.

Top-seeded Taylor Fritz held on to beat No. 7 seed Marcos Giron 7-6 (7), 3-6, 6-3 in a rematch from the quarterfinals of the inaugural Dallas event last year, when Giron won in three sets to set up the first all-American semifinals on the ATP Tour since 2004.

There wasn't a chance for a replay of four U.S. semifinalists in Dallas, with China's Yibing Wu facing eighth-seeded Adrian Mannarino of Italy in the last quarterfinal. Wu rolled to a 6-3, 6-4 victory and will face Fritz.

Wolf, the No. 6 seed, reached his second career semifinal by erasing two break points in the deciding game of another all-American match, closing out the 4-6, 6-3, 6-4 win with his 11th ace on his second match point.

Wolf was broken twice by Tiafoe, a U.S. Open semifinalist last year, while facing nine break points in the first set. The 24-year-old didn't face another break point until the final game.

"I usually don't think about the outcome, so I was just feeding off the energy of the fans and playing every point as hard as I could," Wolf said.

Wolf's opponent is the fifth-seeded Isner, who is back in the semifinals in the second year of his hometown event after a 7-6 (8), 7-5 win over Ecuador's Emilio Gomez, the unseeded 31-year-old son of 1990 French Open champion Andres Gomez.

Isner is the first ATP Tour player to 500 wins in tiebreakers. Roger Federer is second with 466.

Isner and Gomez, playing in his first tour-level quarterfinal, won every point on their own serve in the tiebreaker until Isner took a 9-8 lead on Gomez's serve before serving out the first set.

Isner closed out the match with the only break, and the big-serving American hasn't had his serve broken in any of the three matches.

Fritz, the highest-ranked American at No. 8, reached the semifinals after a disappointing second-round exit at the Australian Open. The 25-year-old won three titles in 2022 and reached the semifinals at Wimbledon.

After dropping the second set, Fritz broke Giron's serve for a 2-0 lead in the deciding set and stayed in front from there.

Wu needed just 73 minutes to eliminate the journeyman Mannarino and reach an ATP semifinal for the first time.

Wu saved all three break points he faced while converting three of four break chances against Mannarino.

The 23-year-old Wu was the first Chinese man to reach the third round at the U.S. Open when he did it as a qualifier last year. Injured for much of 2019-20, Wu is ranked in the top 100 for the first time.