Manny Pacquiao's coach Freddie Roach is unequivocal in his dislike for Brandon Rios.
"I hate him," said Roach bluntly.
"I don't like him or his trainer (Robert Garcia). Once, we were on a press tour with them and they were getting drunk every night.
"A trainer getting drunk with his fighter? That's a disgrace.
"Hanging out with that kid on press tours is like hanging out with a four-year- old."
The animosity between Roach and Rios goes back all the way to Nov 2010, when the fighter crudely mocked the tremors that accompany Roach's Parkinson's disease, in a video that was posted online.
Even though Rios apologised afterwards, it is clear the incident still rankles the five-time Trainer of the Year.
When asked if he was affected by Rios' trash-talking and often expletive- riddled pre-match rants, Pacquiao coolly said: "No. What I do is I pray for him."