Later in 1975, Zorzi arranged a deal with Frank Williams to drive one of his cars at the Italian Grand Prix. The Williams team was struggling at this time, and were using pay drivers to race the ageing FW03 which had failed to score any points so far that season. He qualified the car 22nd of the 28 entrants, just 0.71 seconds slower than his team-mate Jacques Laffite in the newer FW04. Running as high as 12th in the race, he was delayed by a puncture and finished 14th and last, six laps adrift of winner Clay Regazzoni. This was the last race for the car before Williams sold it to Loris Kessel.