The Grand Slam king won't be challenging the King of Clay on dirt this spring.
But Roger Federer has joined rival Rafael Nadal in the arms race.
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The Australian Open champion showed off his guns sporting the rare sleeveless look in this photo with a young fan.
The 36-year-old Swiss shows some sculpted arms and shoulders in a surprise sleeveless look.
Following an Australian Open victory earlier this year, Federer famously told former No. 1 and on-court interviewer Jim Courier he had no plans to forgo sleeves as Nadal has for one simple reason.
"That's not gonna happen," Federer said. "You know why? My arms are not like his arms. It's pretty simple."
Perhaps the father of two sets of twins has bulked up his biceps from carrying his kids, maybe all the fitness work Federer does with physio Pierre Paganini prompted a change of heart or maybe it's just Federer's bid to beat the heat of his Dubai training base.
Whatever the reason, it's kind of cool to see the Wimbledon champion, who sometimes wears a backward baseball cap during practice, sporting a new look.
Will we ever see Federer go sleeveless during match play?
Photo credit: Miami Open Facebook