(Photo credit: Geoff Burke-Imagn Images)

No. 4 seed Ben Shelton needed just 61 minutes to defeat Canadian No. 15 Gabriel Diallo 6-3, 6-2 in the Round of 16 at the Mubadala Citi D.C. Open on Thursday in Washington.

Shelton smashed 16 aces and won an impressive 28 of 30 first-service points (93.3 percent) to make the match an open-and-shut case.

There were no upsets in the early part of the day, as No. 8 Daniil Medvedev of Russia breezed past Chinese qualifier Yibing Wu 6-3, 6-2, and No. 12 Alejandro Davidovich Fokina of Spain and No. 14 Brandon Nakashima also won in straight sets. French lucky loser Corentin Moutet did stay alive in the draw by beating British wild card Daniel Evans 6-2, 7-6 (4).

No. 7 seed Alex de Minaur of Australia pulled out a 7-6 (4), 6-7 (6), 6-4 win over Czech 11th seed Jiri Lehecka, who saved two match points in the second-set tiebreaker to extend the match.

The two evening matches pit home-crowd favorite and sixth seed Frances Tiafoe against Italian ninth seed Flavio Cobolli, and No. 1 seed Taylor Fritz against Italy's Matteo Arnaldi.

Generali Open

No. 1 seed Alexander Bublik won an all-Kazakh battle against Alexander Shevchenko 6-4, 6-2 in 75 minutes to advance to the semifinals in Kitzbuhel, Austria.

Bublik saved all five break points he faced and won a whopping 25 of 26 first-service points (96.2 percent). His next opponent will be Botic van de Zandschulp of the Netherlands, who was a 7-6 (2), 6-2 winner over Brazilian Thiago Seyboth Wild.

French No. 6 seed Arthur Rinderknech outlasted German qualifier Yannick Hanfmann 6-4, 3-6, 6-1, and his semifinal foe will be countryman Arthur Cazaux, who beat German qualifier Jan-Lennard Struff 6-3, 6-4.

Plava Laguna Croatia Open

No. 2 seed Luciano Darderi of Italy rallied from a poor opening set to defeat Croatian home favorite Dino Prizmic 1-6, 6-2, 6-3 in the quarters in Umag, Croatia.

Darderi hit four aces in the decisive third set and is lined up to face No. 3 seed Camilo Ugo Carabelli of Argentina, who led Pablo Llamas Ruiz 6-4, 5-2 when the Spanish qualifier retired.

No. 4 Damir Dzumhur of Bosnia and Herzegovina charged past French qualifier Titouan Droguet 3-6, 7-5, 6-2, and Spaniard Carlos Taberner took down Jesper de Jong of the Netherlands 7-5, 6-3.

--Field Level Media