Alexander Zverev moved past Pablo Carreno Busta 7-5 7-6 (8-6) to become the 10th player in history to reach 30 Masters 1000 quarter finals.
Zverev earned the first break in the third game to open up a 3-1 lead. Carreno Busta pulled back on serve in the 10th game to draw level to 5-5. Zverev broke for the second time in the 11thgame to win the first set 7-5.
Zverev opened up a 2-0 lead with a break in the first game. Carreno Busta pulled back on serve in the eighth game to draw level to 4-4. Zverev earned a mini-break to take a 3-1 lead. Carreno Busta pulled back on serve to draw level to 6-6. Zverev sealed the win with a second mini-break.
Zverev will face either Ben Shelton or Fabian Maroszan.
Zverev claimed the Cincinnati title in 2021 and reached the semifinals last season.
Andrey Rublev moved past Brandon Nakashima 7-6 (7-5) 6-1. Rublev fended off two break points in the first set which went on serve en route to the tie-break. Rublev earned his first mini-break to take a 3-2 lead. Nakashima pulled back on serve to draw level to 3-3. Rublev sealed the tie-break 7-5 with a second mini-break. Rublev broke twice in the second and sixth games and sealed the win on his third match point after 82 minutes. Rublev set up a quarter final match against Jannik Sinner, who advanced after Jordan Thompson withdrew from their third round match with a rib injury.
