Daniel Ricciardo wants clarity over the VSC rules after Nico Rosberg went from a "few seconds" back to right behind him in Austin.
Putting his intermediate tyres to good use on a drying track, Ricciardo made life difficult for the Mercedes drivers in the opening stint of the United States GP.
The Aussie had dropped back to third place when the Virtual Safety Car was used.
While he had a visible gap to Rosberg when it began, by the time the VSC was cancelled the German was right there and surprised Ricciardo as he shot through.
"VSC, you should keep the gap, and Rosberg wasn't right up our arse, he was a few seconds behind," Autosport quotes the Red Bull driver as having said.
"So then when I saw him already close on us under virtual safety car, I was thinking, 'surely he'll back off again'.
"Then he passed me, and then it was green flag apparently.
"I don't know what happened there. I was following suit, basically.
"I think we're going to talk about the Virtual Safety Car in general because it wasn't clear when it was green."
Ricciardo revealed that while the drivers normally have a 10-second warning as to when the VSC will end, it never came in Austin.
He added: "You drive around, you follow this time, and then you actually have to look for the boards.
"It was a bit confusing, I don't know why. On Sunday it was more confusing than it has been in previous races.
"Normally we get a message, I thought, saying 'VSC ending' and a 10-second warning. But there was no warning at all.
"I don't know if Rosberg just caught all of us out, but I was more confused how he was so close to us."