Massa in the 2007 Canadian Grand Prix. At the same race a year later, Lewis Hamilton failed to notice the red light and slammed into the back of the car of Kimi Räikkönen, who was waiting at the end of the pit lane alongside Robert Kubica. From , once cars were lined up behind the safety car, lapped cars were no longer allowed to unlap themselves before the race was restarted. This rule was abandoned from the season onwards, with cars now allowed to unlap themselves before the race resumes. However, since , the safety car does not need to wait for the backmarkers to catch up with the leading pack before returning to the pits. The 2021 Belgian Grand Prix infamously became the shortest race in Formula One World Championship history and the first (and so far only) World Championship Grand Prix in history to be run entirely behind the safety car with no running taking place under green flag conditions, with two full laps completed behind the safety car before the race was red flagged on lap 3 and not restarted thereafter with results taken from the end of lap 1 with Max Verstappen declared the winner of the event and half points awarded to the top 10 classified drivers. In response to the controversial safety car restart at the 2021 Abu Dhabi Grand Prix, the FIA reworked the safety car restart procedure: instead of waiting for the last lapped car to unlap itself, the safety car will now be withdrawn one lap after the instruction to unlap is received. Since 2021, F1 has featured two official safety cars, both the Aston Martin Vantage and the Mercedes-AMG GT R that was already used in previous seasons. From 2022, Mercedes will provide a Black Series variant of their model. Chronology of Formula One safety cars Porsche 914 – 1973 Canadian Grand Prix Porsche – 1976 Canadian Grand Prix Lamborghini Countach – 1983 Monaco Grand Prix Fiat Tempra 16V – 1993 Brazilian Grand Prix Opel Vectra - 1994 San Marino Grand Prix Honda Prelude – 1994 Japanese Grand Prix Lamborghini Diablo – 1995 Canadian Grand Prix Porsche 911 GT2 – 1995 Belgian Grand Prix Renault Clio – 1996 Argentine Grand Prix Mercedes C36 AMG – to Mercedes CLK55 AMG – to Mercedes CL55 AMG – to Mercedes SL 55 AMG – to Mercedes CLK 55 AMG – Mercedes SLK 55