Walsh had withstood the early pressure from the South African factory Audi driver before edging away in the latter laps for what would have been his own maiden win in the championship.
However, after a thorough review of the start of the motor race, 10 competitors were issued time penalties for start line infractions in Thursday's race, while Benny Simonsen was excluded altogether for his Ferrari 458 running underweight.
The penalties also affect the starting order for this afternoon's Race 3, starting at 1205 AEDT, which is set by Race 1 results.
See below for revised results.
Results: Race 1, Round 2, Albert Park