The Red Bull driver, whose team switches from Renault to Honda power for next year, was behind his 2019 teammate Gasly's Toro Rosso as it started to smoke late in the race.

Verstappen had already used all his visor tear-offs by that stage, and could do nothing to improve his visibility.

"It was a bit of oil, I don't know what happened there," Verstappen told Sky Sports after the race.

"I already went through all my tear-offs and there was so much oil on my visor it was like driving through fog, it was horrible.

"I was [trying to wipe it with his glove] but it made it worse so I just stayed off it.

"I asked the team, 'Where is Daniel [Ricciardo, behind], I can't see him in the mirrors, nothing'."

Despite witnessing Gasly's failure up close, Verstappen added he was convinced Honda already has more power than Renault, and he praised the manufacturer's aggressive approach to development that has resulted in Toro Rosso taking several grid penalties for engine changes.

Asked about Honda's reliability, he said: "I think this year has already been pretty good, they have taken a lot of engines just because they could, because they were at the back or something happened.

"I prefer, sometimes, maybe to win a race and then blow up in one than always be consistently slow.

"It looks all very promising but I want to be realistic and just wait.

"First we need to build a great car, and then the engine should be reliable as well, and powerful.

"I think it will be there, but we fist have to do the winter testing and then we'll see."