Ruiz/Sanyo are the more structured, high-IQ pairing: Ruiz can impose with heavy bandeja/víbora patterns while Sanyo controls tempo and transitions. Maxi/Rubini bring lefty-righty balance and speed, but they’ll be tested in Mendoza’s altitude where serve/volley holds and first-strike volleys matter more. Slight edge to Ruiz/Sanyo if they keep Rubini under constant backhand pressure and avoid overplaying risky drop-shots.