Brandon Rios failed his post-fight drug test after losing to Manny Pacquiao in November, testing positive for methylhexaneamine, a banned stimulant. Rios' promoter Bob Arum disclosed that Rios had been suspended by the Macau Commission and blamed Rios' strength coach for the positive test, saying Rios was just following his coach's diet instructions. Both fighters were randomly tested by VADA, with Pacquiao passing all tests but Rios passing the first four and failing the final one.