Maserati was again dominant in the 1st practice session for Race C, reserved to front-engine sport cars having raced between 1952 and 1957, some of them at the Prince Rainier Cup which substituted for the Monaco F1 GP in 1952. Already the fastest in Race B, Spaniard Guillermo Fierro-Eleta clocked a best lap in 2 minutes 5 seconds and 494/1000, driving a very impressive 300 S, although he was confronted to a very competitive set of rivals. The second time was also achieved by a 300 S, driven by Dutchman David Hart, ahead of a Jaguar Type D with Niklas Halusa at the wheel.