Andy Murray does not support the ban on Russian and Belarusian players competing at this year's Wimbledon or other Lawn Tennis Association (LTA) tournaments, while Novak Djokovic reiterated his stance.
The All England Lawn Tennis Club recently announced that players from the two nations are prohibited from competing in the British grand slam following Russia's invasion of Ukraine.
It means the likes of men's world number two Daniil Medvedev and women's world number four Aryna Sabalenka would miss out on the British swing.
Djokovic and Rafael Nadal have both spoken out against the ban, while the ATP and WTA have also pressed for reconsideration.
Now Murray, a two-time Wimbledon champion who also won Olympic gold at SW19 in 2012, has refused to give the ban his backing.
"I'm not supportive of players getting banned," Murray said in a news conference ahead of the Madrid Open, with the former world number one in action against Dominic Thiem on Monday.
"My understanding of the guidance was that Russians and Belarusians can play if they sign a declaration that they're against the war and against the Russian regime.
"I'm not sure how comfortable I would feel if something happened to one of the players or their families."
Murray understands it is a delicate situation, however.
"I don't think there's a right answer. I have spoken to some of the Russian players. I've spoken to some of the Ukrainian players," he continued.
"I feel really bad for the players who aren't allowed to play and I get that it will seem unfair to them. But I also know some of the people who work at Wimbledon, and I know how difficult a position they were in.
"I feel for everyone, feel for the players that can't play, and I don't support one side or the other."
There has been speculation that the ATP and WTA may sanction Wimbledon, with one possibility being reducing the amount of tour points on offer from the grand slam.
World number one Djokovic, who will be allowed to compete at Wimbledon, where no requirement for a COVID-19 vaccination will be in place for players, is unsure what the next step will be.
He told reporters: "I've spoken to some of the Russian players in Belgrade [at the Serbia Open].
"Obviously, it's not an easy situation to be in. Being stripped of the right to participate in one of the biggest tournaments, if not the biggest tournament in the world, it's hard, I understand that. There is frustration.
"[The] ATP is going to analyse the whole situation and understand what can be done. I have not spoken to people from ATP so I'm not sure about it. I've gone through something similar, it's not the same thing, but something similar earlier this year for myself [when he was denied entry to Australia due to his COVID-19 vaccination status].
"It's frustrating knowing that you're not able to play. I still stand by my position that I don't support the decision. I think it's just not fair. It's not right. But it is what it is, they are entitled to make the decision.
"I guess it's on Player Council, the tour management, to really decide, along with the players, what is the best solution in this situation whether they keep the points, protect the points, take away 50 per cent of the points.
"So I heard that some of those models are still considered to be used in this kind of instance, but I'm not sure what is right, what is wrong, to be honest. I guess we'll have to wait and see the outcome."