Daniil Medvedev concluded his 2025 Shanghai Masters campaign with a semifinal loss to Arthur Rinderknech on Saturday, October 11. After the match, the Russian had a heated discussion with the chair umpire, Mohamed Lahyani, which garnered disappointed reactions from the tennis community online.Medvedev had an impressive run in Shanghai, as he defeated Dalibor Svrcina, Alejandro Davidovich Fokina, Learner Tien, and Alex de Minaur to reach the last four. He lost the semifinal to Rinderknech 6-4, 2-6, 4-6.After the match, Medvedev was seen in an animated discussion with Lahyani, as the former World No. 1 was apparently unhappy with some of the calls made. Lahyani had also given him a code violation during his Round-of-16 clash against Tien for not getting ready in time to return serve.The Moscow, Russia, native, who has had several confrontations with officials in the past, attracted discontented reactions from the fans about his behaviour.A fan mentioned:"Worst sportsmanship on the tour year after year. Does he EVER lose gracefully? What an a-hole."Another added:"Always something to cry about. Immature!"A tennis enthusiast wrote:"Daniil needs help."Some of the other reactions to Medvedev's outburst are as follows:"man you better shut your puck up," wrote another."lahyani couldn't give a f**k," another fan mentioned.Following his Shanghai Masters loss, Daniil Medvedev will compete at the 2025 Almaty Open, an ATP 250 tournament, which will take place from October 13 to 19 in Almaty, Kazakhstan.Daniil Medvedev reacts to receiving a code violation during his match against Learner Tien from Mohamed LahyaniDaniil Medvedev at the 2025 Shanghai Rolex Masters - Day 10 - Source: GettyDuring his fourth-round clash with Learner Tien in Shanghai, Daniil Medvedev received a code violation from chair umpire Lahyani, who thought he was taking longer on the return when Tien was ready to serve.Medvedev mentioned former player Rafael Nadal and said (via The Tennis Gazette):"All my life, I've been serving & waiting for Rafa for 55 seconds. And you give me a code violation on the first occasion. I played Rafa 5 times, there was not one time I was ready to serve and he was ready to return. He didn't get one time violation. To me, today, at the slightest thing you give it to me. I always waited to return, and you didn't give it to him. You're crazy. Completely crazy." During his China Open semifinal match against Tien last month, Medvedev received a code violation from umpire Adel Nour for a lack of effort due to cramping. However, in a statement to The Athletic, the ATP revealed that the violation was made erroneously and that no fine will be imposed on the Russian.