The Colombia international is confident that the on-loan Porto defender, who he played alongside at the Estadio do Dragao, will prove to be a fine addition for the Nerazzurri
The centre-back, 27, joined Inter from Porto on a one-year loan deal earlier this month and the Nerazzurri have the option to make the deal permanent should the temporary move prove to be a success.
Guarin is confident that the Portugal international will provide extra quality at the back for Walter Mazzarri's side.
"Aside from being a good friend, Rolando is a great player as well," Guarin was quoted as saying by A Bola.
"He will prove to a good addition for Inter. The team really needed a player with his quality. He will be well received in Milan."
Guarin and Rolando previously played together at Porto from 2008 until 2012.
The defender could make his official Inter debut in this weekend's Coppa Italia game versus Cittadella.