As if Roger Federer needed to do anything more to win the hearts of tennis fans worldwide, the Swiss superstar has once again shown why he's regarded as one of the sport's classiest ambassadors.
The world No.8, who is continuing to battle his way back from a lengthy injury layoff following the 2020 Australian Open, made the day of retiring star Alexandr Dolgopolov.
Federer is no stranger to reaching out to his fellow players on social media, having sent a heartfelt message to Australian star Thanasi Kokkinakis following his own return from injury earlier this year.
There was an outpouring of congratulations and support for the retiring Dolgopolov, nicknamed 'The Dog' on social media - but the 32-year-old was most surprised by a message from Federer.
“Congratulations on a great career, thanks for all the fun times on the practice courts and team RF always loved watching you play but you know that,” Federer wrote.
“Take care, best regards and hopefully we see each other again. All the best for what’s to come Dog.”
Dolgopolov was clearly rapt to receive the message of farewell, sharing it with his 27,000 followers on Instagram and paying a tribute of his own to Federer in the process.
The Ukrainian reached a career high ranking of 13 in 2016, having remained in the top 70 from 2010 to 2017 after turning pro in 2006.
“Guys, honestly, I never thought so many people admired my tennis!” he wrote.
“In 3 years off tour, I have forgotten what I did on the tennis court, and the amount of wishes I got today is unreal!
“I am really, really, really touched by all the messages, but one of them is special for me and simply made my day.
“With @rogerfederer permission, I repost these wishes, because I immensely respect this person, he is a legend, very kind and we spent some years preparing for the season together and the advice and conversations I got was priceless!
“Giant thanks to @rogerfederer and his team and best of luck.”
Dolgopolov and Federer faced each other five times, with the Swiss champion prevailing in all five matches.
Roger Federer set to auction off grand slam memorabilia
Millions of Roger Federer fans around the world might be salivating at the prospect of owning some mementos of the Swiss great's incredible career after he announced he is auctioning off a collection of personal items this summer.
The 20-times grand slam champion, regarded by many as the greatest player ever to wield a tennis racket, is putting various items under the hammer in two sales in June and July at Christie's to raise money for his foundation.
A live auction taking place on June 23 will feature 20 lots, with each one reflecting one of Federer's grand slam titles. Prices will range from STG3,000 pounds ($A5,300) to STG70,000 pounds ($A119, 000).
Lots include the outfit and racket from Federer's 2009 French Open final victory over Robin Soderling which completed his career grand slam, including the shoes still coated in red Roland Garros clay dust.
Fans and collectors will also be able to bid for the 2007 kit and racket he used during the second of his three Wimbledon finals against career-long rival Rafa Nadal, including shoes decorated with Swiss flags denoting his Wimbledon titles.
Federer's elegant white RF-emblazoned cardigan, worn before facing Britain's Andy Murray in the 2012 Wimbledon final, is also up for grabs, as are the shoes he wore when winning his third successive Wimbledon in 2005 against Andy Roddick.
"Every piece in these auctions represents a moment in my tennis career and enables me to share a part of my personal archive with my fans around the world," Federer said.
"More importantly, the proceeds will support The Roger Federer Foundation to help us continue to deliver educational resources to children in Africa and Switzerland."
A second online auction takes place in July featuring 300 lower-priced items such as the wristbands Federer wore during his 1,500th professional match at a tournament in Basel.
Christie's low estimate values the entire collection at STG1 million pounds ($A1.7 million) but hopes to reach STG1.5 million pounds ($A2.70 million).
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