John Isner served up strong support of Novak Djokovic.
In a social media post, Isner said "there is no justification for the treatment [Novak] is receiving" calling Djokovic's case "such a shame."
More: Djokovic Denied Entry Into Australia
Twenty-time Grand Slam champion Djokovic was initially approved to play the Australian Open on a medical exemption. However, Australia's Border Force denied his visa upon his arrival in Melbourne and now Djokovic sits in a hotel as his attorneys file a visa appeal on his behalf.
The 34-year-old Serbian superstar and Isner are good friends and members of the Djokovic-led PTPA.
The PTPA posted this statement on Djokovic's case.
Photo credit: Lindsey Godwin/Miami Open