Rodrigues was signed on a free transfer by Southampton at the age of 30 in 1975, after being released from his contract by Sheffield Wednesday. The Welsh international full-back was signed by Lawrie McMenemy as cover for Steve Mills, who had been injured in a car crash and was out of action for a lengthy period of time. Rodrigues' first season at The Dell could not have been better, with the side winning their first and only FA Cup. Rodrigues played at right-back in the Wembley final, and captained the team, as Southampton beat Manchester United 1–0. However, Rodrigues' second year at The Dell saw his playing days ended with a persistent knee injury.