The running feud between Alexis Ohanian, the multi-millionaire husband of Serena Williams, and former Romanian professional Ion Tiriac, has deepened with the latter's son now weighing in.
The back and forth began earlier this year after Tiriac was heavily criticised for suggesting Williams was overweight, out of shape, and 'too old' to compete at the highest level.
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The 81-year-old went on to say Serena should retire 'if she had a little decency'.
Tiriac's comments were widely criticised among tennis fans, however they seem to have stuck with Ohanian, who called out Tiriac by name following Williams' quarter final win at the Australian Open.
With Williams defying the call for her to retire with an impressive Australian Open campaign, Ohanian took to Twitter to once again take aim at the former pro.
"Good thing no one listens to that racist sexist (clown emoji) Ion Tiriac," Ohanian wrote in a tweet accompanied by highlights of Williams' win over Simona Halep.
That comment prompted a response from Tiriac's son Alexandru, who published an open letter addressed to Ohanian in which he attempted to defend his father from criticism.
The politely worded letter nonetheless described Alexandru's 'disbelief and disgust' upon seeing Ohanian's tweet, and argued the elder Tiriac had 'tremendous' respect for Williams - contrary to popular belief.
"I read your tweet with a mix of disbelief and disgust," the open letter read.
"The name Țiriac has a 70-year tradition in the world of sports and the gentleman you are referring to has written a few important chapters that have contributed to the book of tennis along these decades.
"From the player, to the coach, to the manager, to the tournament promoter, the respected person you are bad wording in these derogatory terms has and still is, at the age of 82, one of the strongest advocates of this sport.
"The respect he has for Mrs. Williams is tremendous, as it should be."
Alexis Ohanian's feud with Ion Tiriac deepens
Alexandru went on to criticise Ohanian for his words, saying he had 'misused and misinterpreted' his father's comments and argued it was unfair for the Reddit co-founder to direct his considerable public following against his father.
"Mr. Williams, the only reason I reply to your unnecessary tweet is that words are misused and misinterpreted in today’s world through the various platforms in existence," Alexandru wrote.
"Free speech should not be wrongly replaced with inappropriate slander.
"As Mrs. Williams’ husband, you can no longer only represent your own views when you talk about sports, but also the voice of an icon.
"It would be a real shame to cast an erroneous image on her legacy through emotional baseless tweets.
"I hope that through these few sentences I can bring some wisdom to your future misguided public declarations, and maybe some due respect to a self-made man who is a true lover and lifelong contributor to this sport.
"Congratulations to Serena, very well deserved, keep going forward and writing history in such a wonderful career."
Ohanian did not appear to have responded to the letter, which circulated on social media on Wednesday.
In the meantime, Serena Williams is preparing for her semi-final clash against young rival Naomi Osaka, which is scheduled for Thursday night.
Czech star Karolina Muchova will face America's Jennifer Brady in the other semi-final.
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