Daniil Medvedev's behavior during his clash with Benjamin Bonzi at the 2025 US Open has sparked controversy. Tennis fans did not take kindly to the Russian mocking Bonzi's celebration with a seemingly profane gesture.Medvedev, who crashed out in the first round of the last two Grand Slams, was hoping to rebound with a deep run at the New York Major. Despite mounting a thrilling comeback after his heated outburst at the chair umpire in the third set, the Russian ultimately suffered a 6-3, 7-5, 6-7(5), 0-6, 6-4 loss to Bonzi in his opening match.In a match that was rife with drama, Daniil Medvedev grabbed attention after he was spotted mocking Benjamin Bonzi's fist pump with an expletive gesture while trailing in the contest.Did.... Medvedev just do what I think he just did?? byu/cdsparks intennisMedvedev's actions did not sit well with fans, as they harshly criticized the Russian for "mocking" Bonzi without any provocation."Smashing rackets and letting out frustration that way doesn’t bother me…. But mocking your opponents and being disparaging about them after a loss is just not cool," one fan posted."He is so embarrassing. His opponent wasn’t even antagonizing him," another fan chimed in."Omg he is awful and gross," a fan shared."I know this sub loves Medvedev but no other player mocks their opponent more than he does. It’s so childish," said yet another.Fans also denounced the former World No. 1 for being a "sore loser" and argued that he should've received a hefty fine or a warning from the umpire after the contentious gesture."Such a sore loser I swear what a manchild," one fan commented."Completely unacceptable. Hope there is a significant fine," another fan wrote."How is that not a fine? gross. totally over him," a fan posted."Kind of surprised he didn't get a visible obscenity for this, especially because Allensworth is the umpire tonight," said another.The match also saw a major moment of controversy when Daniil Medvedev launched a furious tirade at chair umpire Greg Allensworth over a contentious ruling and cause a significant delay after riling up the US Open crowd.Benjamin Bonzi to face Marcos Giron in US Open 2R after win over Daniil MedvedevDaniil Medvedev and Benjamin Bonzi - Source: GettyFollowing his impressive win over Daniil Medvedev, Benjamin Bonzi will take on Marcos Giron in the second round of the 2025 US Open. Giron claimed a hard-fought 6-0, 7-5, 4-6, 5-7 win over Mariano Navone to set up a meeting with the Frenchman.If Bonzi triumphs over Giron, he will lock horns with the winner of the match between Alejandro Davidovich Fokina and Arthur Rinderknech in the third round of the New York Major. The 29-year-old could then meet Carlos Alcaraz in the fourth round, followed by a potential quarterfinal clash with Ben Shelton or Casper Ruud.Meanwhile, Daniil Medvedev will have some time off before returning to action at the Hangzhou Open. The Russian will be joined by the likes of Karen Khachanov and Andrey Rublev at the ATP 250 event, which is scheduled to kick off on September 17.