Ukraine's Marta Kostyuk praised Daria Kasatkina's "courage" in switching nationalities from Russia to Australia and hinted she may shake hands with her after their match at the Italian Open.
Kasatkina changed allegiance in April, having been critical of her country's LGBTQ+ laws and the war in Ukraine.
Ukrainian players have a long-standing policy of not shaking hands with Russian or Belarusian players, with Kostyuk describing it as "a personal stance against Russia's aggression".
Kostyuk wrote on Instagram: "When someone not only tells the truth - calling Russia the aggressor - but also acts on it, that deserves respect.