Why Federer stopped practicing with Murray and 'never' trained with Nadal, Djokovic – TNT Sports

Why Federer stopped practicing with Murray and ‘never’ trained with Nadal, Djokovic  TNT SportsAndy Murray couldn’t be ‘friends’ with Federer, Nadal and Djokovic as invitation sent  Daily ExpressAndy Murray reveals Roger Federer mind games that Ronnie O’Sullivan also used with snooker rivals  The SunAndy Murray opens up about his greatest rivals saying they couldn’t be ‘friends’  Daily Record“After a year or two he stopped, he wouldn’t practice with me anymore” – No sparring with enemies: Federer’s unwritten ‘Big Three’ code  Tennisuptodate.com