Rodriguez joined Liverpool on 13 January 2010 from Atletico Madrid, but prior to the deal being sealed Benitez was insistent that every player spoke English.
"English football always enticed me and I like those kinds of challenges," said Rodriguez to Argentinian media outlet Ole.
"Rafa told me that it was very important, that he wanted everyone to speak English in the dressing room.
"He asked me if I knew (English) and I said 'Si', to keep him calm. Of course, I did not want the transfer to fall through.
"We arrive in England and the press conference is held. There he tells me that he was starting and then I was next. Then I grabbed him and said: 'Look, Rafa, I have a confession to make: I don't know English. The only thing I know how to say is hello, I didn't want the operation to fall down.' And he answered me: 'No way, you're a son of a bitch.'
"We were laughing there, but well... I had to learn."
Rodriguez spent two and a half years at Liverpool, playing 73 matches and scoring 17 goals.
