Australian tennis star Nick Kyrgios has criticised Dominic Thiem for the Austrian's refusal to contribute to a fund set up to assist lower-ranked players struggling financially because of the coronavirus lockdown.
Men's world No 1 Novak Djokovic last month outlined a proposal aimed at raising up to $4.5 million (Dh16.5m), primarily for players ranked outside the top 100. Players would contribute incrementally more based on their ranking, with the world's top five players required to put in the most.
World No 3 Thiem earlier this week said he was reluctant to contribute, calling into question the "professionalism" of many lower-ranked players and saying he would rather donate money to more worthy causes.
Kyrgios, who has earned a reputation for speaking his mind, has disagreed with Thiem's stance, saying on Instagram: "He still doesn't understand the point. We at the top get paid far too much and there is not enough to go around.
"It's about helping where we can, professional or unprofessional, put yourself in their shoes."
Kyrgios, 25, may have earned a bad boy image throughout much of his career, but the world No 40 has shown to be a leader in times of crisis this year.
He led the Aces for Bushfire Relief initiative to raise funds for communities affected by the Australian fires at the start of the year and has been delivering food and essentials to people during the coronavirus pandemic.
Professional tennis has been in lockdown since the start of March and will not return until at least the end of July due to the Covid-19 outbreak.