Prior to the free agent switch, Rodriguez assured Benitez that there would be no problems with the language barrier.
"I was very happy at Atletico because I was the captain and I knew the city, but I was always crazy about English football," Rodriguez told former team-mate Juan Pablo Sorin on Instagram live.
"Rafa told me that it was very important that everyone spoke English in the changing room. "He asked me if I could and I said 'yes,' to be calm. Of course, I didn't want the transfer to collapse!
"We arrived in England and I had the press conference. He [Benitez] said he would start and then I would follow.
"It was then that I grabbed him and told him, 'Look Rafa, I need to confess: I don't speak English.The only thing I can say is hello'.
"I didn't want the transfer to move to fall through! He replied: 'No, you are a son of a b——.'
"We both laughed and then, well, I then had to learn!"