By Tennis Now | Wednesday, May 23, 2018

Taylor Fritz had the final word on first serve surprising third-seeded Jack Sock in Lyon.

In an all-American clash, Fritz fired eight aces, won 70 percent of his second-serve points and did not drop serve defeating Sock, 7-6 (6), 6-2.

Watch: Four Burning French Open Questions

It was Fritz's second straight clay-court win over the Paris Masters champion, following his 6-3, 3-6, 6-4 victory over Sock in the Houston quarterfinals last month. Sock won their prior two meetings, which both went five sets, at the 2016 Australian Open and US Open.

The 15th-ranked Sock fell to 5-10 on the season with just one quarterfinal appearance in 10 tournaments in 2018.

Four of Sock's 10 defeats have been to fellow Americans: He lost to Reilly Opelka in Delray Beach, was beaten by Ernesto Escobedo in Indian Wells and has suffered successive defeats to Fritz.

The 20-year-old Fritz advanced to his third Tour-level quarterfinal of the year where he will play Dusan Lajovic for a spot in the final four. Lajovic was a 6-4, 7-5, victor over 334th-ranked Slovakian qualifier Filip Horansky earlier today.

American men comprise two of the last eight.

Miami champion John Isner blasted 22 aces and won 11 of 15 second-served points repelling Radu Albot, 7-6 (3), 6-3.

Isner advanced to his fourth quarterfinal in his last five tournaments.

The towering Isner will face Cameron Norrie for a semifinal spot.

The left-handed Briton beat Germany's Maximilian Marterer, 6-1, 6-4, in one hour.