Once consigned to intense but respectful competition on the court, the tete-a-tete between these two tennis greats has taken a turn for the worse, with Rafa criticizing FedEx's silence with regard to tour conditions ahead of the 2012 Australian Open.
According to the Associated Press, Nadal expressed both discomfort with heading up the players' grievances about an overcrowded schedule and disgust with Federer for not being at all vocal about the matter. Said Rafa of Federer's position:
"For him it's good to say nothing. Everything positive. 'It's all well and good for me, I look like a gentleman,' and the rest can burn themselves."
This, amidst whispers of a potential players strike, whispers in which Nadal and Andy Murray, the No. 4 seed at Melbourne Park, have played prominent parts.
"He (Federer) likes the circuit. I like the circuit," Nadal said. "It's much better than many other sports but that doesn't mean that it couldn't be better. It doesn't mean there are some things about the tour that could change. The tour is fine, but there are some things that are bad. That's all we're saying.
"And the vast majority of players have this same opinion. He's got a different opinion ... if the vast majority have one opinion, and a small minority think differently, maybe it's them who are wrong."
Harsh words for Federer, the all-time winningest Grand Slam champion in men's tennis history with 16 wins in the four major tournaments, including four victories down under.
But Rafa's digs at Federer didn't end there. In discussing the toll that tennis has taken on his body, Nadal went on to "diss" Federer for playing the game with finesse rather than physicality.
"Maybe (Federer) has got a super body and he'll finish his career like a rose. Neither myself, nor Murray, nor Djokovic are going to finish our careers like a rose."
All of which points to one thing: a potential semifinal match between Nadal and Federer wherein the bad blood will practically be boiling over with hatred.
As if trying to close the gap on his rivalry with Nadal, in which Rafa currently owns a 17-9 edge, weren't motivation enough for the Swiss sensation.