(CNN) -- Toni Nadal is used to letting his famous nephew do the talking with his tennis racket -- and it sounds like it should stay that way.
The uncle and long-time coach to 14-time grand slam champion Rafa Nadal is in hot water after serving up some controversial comments on Spain's new Davis Cup captain, Gala Leon Garcia.
Garcia, who was announced as successor to Carlos Moya earlier this week, is the first female to captain Spain's men's team. She is the fifth woman to coach a Davis Cup side, according to the International Tennis Federation.
But Nadal thinks appointing the 40-year-old -- whose highest ranking as a player was 27th -- could pose problems, not least in the locker room.
"In no way am I sexist," Nadal told Spanish radio station Cadena SER on Tuesday.
"You could brand me old-fashioned in seeing problems about having to share a dressing room with a woman, but to go from there to talking about sexism ... Would I be OK with peeing in front of a woman? No way. That in any case might be old-fashioned."
Comfort breaks aren't the only issue, according to Nadal.
"A woman is just as capable as a man, but men's and women's tennis are different sports," he argued.
"I know nothing about the hours and training systems for women's tennis. I don't even know who the best players are. I doubt Gala Leon knows the (men's) world number 40 ..."
Nadal, 53, was responding after his initial comments on the subject aired on Monday caused a bit of a stir.
In a interview with on RNE, Spain's national radio station, Nadal initially suggested it "might be easier for the captain to be a man," before addressing the issue of the locker room for the first time.
"I believe she doesn't know the players, at least Rafael, and there is a logistical difficulty that is difficult to solve, because in the Davis Cup a lot of time is spent in locker rooms without much clothing and with a woman it would always be weird."
But some players who may play under Garcia appear unfazed by the prospect.
"I don't think the fact she is a woman affects anything," doubles specialist Marc Lopez said, Spanish newspaper El Pais reported.
"The players have to accept it, to be united, to play, win and go up to the World Group," the 32-year-old added.
"There are several rooms ... it's not essential that she is there where you're having a shower. It will be a bit different, but I don't think whether she can or can't be there all the time will influence the development of her work."
Britain's Andy Murray, who appointed former women's world No. 1 Amelie Mauresmo as his coach in June, was supportive of Garcia's appointment.
Murray's recent tweet about Scottish independence might have been controversial but few would have disagreed with his views on the vote of confidence in Garcia by Spain's Davis Cup bosses.
"Congrats to Gala Leon Garcia for becoming first female Spanish Davis cup captain today... hopefully first of many!" Murray tweeted.
Spain has dominated the Davis Cup in the early 21st century, winning the team tournament five times since 2000, but has struggled in recent times.
In September, Spain was relegated from the World Group for the first time since 1996 after losing 3-1 to Brazil.
The wrist injury that kept Rafa Nadal out of the U.S. Open also precluded his involvement in Spain's defeat in Sao Paulo, but the world No. 2 is expected to return to action at next week's China Open in Beijing.