Formula 1 race director Charlie Whiting has revealed that he aborted the first start of the Australian Grand Prix because he was uncertain that it was safe to proceed after a marshal had triggered a warning light.
The original getaway was abandoned, with the drivers being sent around for another formation lap, after Sergio Perez hesitated to get into the right grid slot and then a yellow warning signal for Daniil Kvyat went off.
Whiting said that the combination of events meant he was not totally sure that it would have been safe to proceed with the race at that point.
"I aborted the start because there was uncertainty, and I always want to be certain, or as certain as one can be, that all is well before pressing the start button," Whiting told Autosport.
"Firstly, Perez had pulled up in the wrong position but, after a few seconds in that position, began pulling forward.
"At the same time, the marshal responsible for the light panel beside Kvyat's car pressed the yellow button which indicated a problem.
"Neither I nor my colleagues in race control could see a problem so I felt the safest option was to abort and send them off on another formation lap."
There was no firm answer as to why the marshal had triggered the yellow warning signal for Kvyat - but the situation could have been caused by heightened anticipation following a small fire on the car as the team had worked on it on the grid.
Whiting added: "It was clear from the video that there was nothing wrong with Kvyat's car nor did he make any signal, so it may well have been a case of nerves on the part of the marshal.
"It doesn't fully explain why the button was pressed but people sometimes do inexplicable things under pressure.
"In any case though, the main point is that there was uncertainty as to whether it was safe to give the start so it was aborted.
"No driver appeared to be to blame so hence no driver was required to start from the pit lane."