Russian world number eight Andrey Rublev said Wimbledon's ban on Russian and Belarusian players is "complete discrimination" and "illogical".
Rublev is one of three top-10 players - along with fellow Russian Daniil Medvedev and Aryna Sabalenka of Belarus - who cannot play at SW19 this summer.
Wimbledon made the decision to ban Russian and Belarusian players because of the invasion of Ukraine.
"The reasons they gave us had no sense, they were not logical," said Rublev.
"What is happening now is complete discrimination against us."
Rublev's comments to the AFP news agency came after the 24-year-old won 4-6 7-6 (7-1) 6-2 against Czech opponent Jiri Lehecka at the Serbia Open.
Shortly after the war started in February, Rublev appealed for peace when he signed a camera lens with a "no war please" message at the Dubai Tennis Championship.
On Wednesday, world number one Novak Djokovic said he did not support the "crazy" decision by the All England Lawn Tennis Club (AELTC) to ban Russian and Belarusian players.
Martina Navratilova, who won a record nine Wimbledon singles titles, said excluding Russian and Belarusian players was "not the way to go".
Wimbledon, which is one of the sport's four Grand Slam events, runs from 27 June to 10 July.
Meanwhile, six-time Wimbledon champion Djokovic reached the Serbia Open semi-finals when he fought back from a set and a break down to beat fellow Serb Miomir Kecmanovic.
The 20-time Grand Slam champion, who came back from a similar deficit against Laslo Djere on Wednesday, won 4-6 6-3 6-3 against world number 38 Kecmanovic.
Djokovic, chasing a third title at the Serbia Open and a fourth ATP Tour title overall in his home city, will face either Russian third seed Karen Khachanov or Brazilian qualifier Thiago Monteiro for a place in the final.
At the Barcelona Open, British number one Cameron Norrie's match against Hungary's Marton Fucsovics was pushed back to Friday after Thursday's play was ruined by rain.
