Tennis will probably change one of its anti-doping rules in 2014 following Viktor Troicki 's ban . the International Tennis Federation ( ITF ) says that was n't the case . The ATP said it would allow players to use the banned substance meldonium if they had a doctor's note from their doctor saying that Meldonium, which is used as an appetite suppressant and for Troicki claims he was told he could take the test the day after but the ITF refutes that . Troicki says Novak Djokovic was among those who signed a petition demanding rule changes .
Tennis will probably change one of its anti-doping rules in 2014 following Viktor Troicki 's ban . The ATP said it would allow players to use the banned substance meldonium if they had a doctor's note from their doctor saying that Meldonium, which is used as an appetite suppressant and for Troicki claims he was told he could take the test the day after but the ITF refutes that . Troicki says Novak Djokovic was among those who signed a petition demanding rule changes .