Benitez revealed he has kept in touch with his former Liverpool midfielder, who attempted to sign the talented midfielder.
"We have kept in touch. Both of our lives are very busy and it isn't about giving advice but we have had contact to talk football and to talk about players," Benitez told The Athletic.
"In fact, in the summer of last year, Stevie called me about Sean Longstaff.
"Some people have said, 'Oh, Rafa was lucky because of Longstaff' but we'd been watching him and we were happy with him, we played him in the first-team, supported him and gave him confidence.
"Turning Rangers down is proof of what we thought of Sean."