Sao Paulo, Brazil - Red Bull's Daniel Ricciardo and Toro Rosso rookies Pierre Gasly and Brendon Hartley are all braced for grid drops at the Brazilian Grand Prix.
Ricciardo told reporters he expected to have to take a hit for the penultimate race of the season after engine problems halted his Renault-powered car at the previous round in Mexico.
"I may have to take another penalty. It is likely," he said. "We could maybe avoid it but it is probably going to put us in a risk again of not finishing. We tried to avoid it last weekend and it still didn’t happen. I probably won’t have a big one, but if it is, it could be like 10 places."
Ricciardo's Dutch team-mate Max Verstappen has won two of the past four races, including Mexico, while the Australian has suffered a sudden run of reliability problems.
Gasly and Hartley also spoke of the likelihood of penalties once Friday practice is out of the way.
"It looks like we will have to start from the back of the grid," Gasly said, "which makes it of course pretty difficult. But it is something that we cannot really change."
Toro Rosso will switch from Renault power units to Honda next year - but right now is fighting for sixth in the Constructors' championship and leads seventh-placed Renault by just five points.