Second-round action got underway on Saturday at the Lindner Family Tennis Center, where high temperatures characteristic of the North American summer added an extra challenge for the players to overcome.
Two seeded players fell early, those being world No. 10 Lorenzo Musetti, ousted by the spirited Frenchman Benjamin Bonzi 5-7, 6-4, 7-6(4) in two hours and 46 minutes on Court 10.
Both players struggled to hold their ground behind their serves, but in the 12th game, the Italian converted his third break, wrapping up 7-6(4) in 48 minutes.
As the second set wore on, the world No. 63 found his foot, breaking twice to open a 5-1 advantage over the eighth seed.
Then, showcasing his tennis IQ, Musetti posed a late challenge, capitalizing on the Frenchman’s errors, coming back from 1-5 to 4-5 down.
Bonzi, who launched his campaign in Ohio on Thrusday with a convincing three-set win over Italian Matteo Arnaldi, did not hesitate when serving for the set 6-4, saving a break point in the 10th game to level up one set apiece.
A third set decided by small margins saw the players opening with a trade of breaks exchanged.
The edgy decider led into a final tiebreak, the 29-year-old took with authority 7-6(4), recording his second victory over a Top 10 player of the season.
Meanwhile, the fifth meeting at the tour level between 11th seed Casper Ruud and world No. 70 Arthur Rinderknech saw the latter come out on top, 6-7(5), 6-4, 6-2 in two hours and 37 minutes, recording his first career victory over the Norwegian.
The Mutua Madrid Open champion arrived in Cincinnati from Toronto, where he lost in the round of 16 to eventual runner-up Karen Khachanov.
The Canadian Masters 1000 marked the return to action of the former US Open finalist, competing in his first tournament since skipping Wimbledon due to a knee injury sustained in Roland-Garros.
At the Lindner Family Tennis Center, the 13-time ATP titlist opened his campaign with a solid performance, showcasing high-level tennis to pocket a tight first set tiebreak 7-6(5) in 65 minutes.
Nonetheless, from the get-go, the man who stunned world No. 3 Alexander Zverev in the first round at Wimbledon, went toe-to-toe, showing an edge at the net, winning 7 of 13 approaches.
En route to record his first win against Ruud in five meetings, the 30-year-old pushed an extra gear, rallying from a set down to wrap up the action in three sets.
All in all, Rinderknech hit 36 winners against 31 unforced errors, winning 78 percent of the points on his first serve, and converted all four break point opportunities he had.
Both French players have progressed into the third round at the Masters 1000, and now await their next opponents.
Bonzi will play 25th seed Stefanos Tsitsipas, who took down Fabian Marozsan 7-6(3), 6-2.
Elsewhere, Rinderknech will square off against 23rd seed Felix Auger-Aliassime; the Canadian beat Argentine Tomas Martin Etcheverry in straight sets.
The 24-year-old, born in Montreal, leads the former world No. 42, 1-0 in their series.