Andy Soucek admits he accidentally pressed the kill switch twice on the #108 Bentley Continental while leaving the pitlane during the Bathurst 12 Hour, costing the squad a victory chance.
Soucek rolled to a halt at the pitlane exit twice during today's race with the first time coming just after the two-hour mark when he had first taken over the car.
At the Bentley's final pitstop Soucek repeated the error and, instead of slotting into second with then-leader Jake Dennis in sight, he ended up rejoining in seventh and more than a minute off the lead.
He had also earned a mid-race drive-through for passing a car before the control line on a restart.
Soucek told Autosport he owed his team-mates an apology for twice hitting the switch located on the steering wheel.
"I'm gutted," he said. "We travelled around the world to come to Bathurst.
"Everything was ready, my team-mates did a mega job, the strategy and car was there.
"Sometimes you don't have a good day, and it wasn't a good day for me personally.
"I drove well, but I made way too many mistakes.
"In all of my stints I did something.
"I got a drivethrough for passing a car before the line - a slow car, the differential in speed was way too high - but it was my fault.
"I should have waited.
"And then I pressed the stop button twice going out of the pits. The car stopped and I had to make full reset, so all of the blame is on me.
"I want to apologise for my team, who did a great job, and my team-mates.
"It's going to be a tough 20-hour flight home."
Soucek said he could not blame Bentley for an operational error because the drivers requested the kill switch button.
"I don't want to blame the car," he said. "We asked to put a button on the steering wheel to be able to stop the car quicker.
"It never happened before. Sometimes you just have that bad luck where it's not your day.
"And I hit it twice. I don't know what to say. It's an amateur mistake.
"I've won most of the championships I did myself in single-seaters, I'm experienced in GTs, so it shouldn't happen.
"I'm disappointed in myself.
"I can't blame anyone for putting the button there, it's for us to stop the car. My fault."
Soucek admitted that the Bentley was in contention to win the race without his error.
"We would have been seven seconds behind the Aston going out of the pits if I didn't hit the button," he said.
"Then there was this [late] safety car and I probably could have had a chance to overtake him the same way [Matt] Campbell did at the end.
"I don't know if we would have won, but we would have been in contention for sure because we had good straightline speed and the car was mega."