But Hamilton has refused to give up hope of retaining the lead of the championship race in his quest to become the first British driver to win four world titles.
Ferrari's engineers, both at the track and back at the factory in Maranello, had run through numerous set-ups, as test driver Charles Leclerc (who is set to win this year's Formula 2 title and will race for Sauber in F1 in 2018) undertook countless runs in the simulator.
But Verstappen was told to return to the pits slowly after reporting that the auto was "shifting by itself" while Red Bull teammate Daniel Ricciardo clipped the wall, forcing him to back out of his final attempt a low-fuel run. "We are still not where Ferrari or Mercedes is".
Vettel had struggled considerably during second practice session, placing only 11th under the sticky floodlights.
"Today's Friday, we tried various options, different tyres but, come Sunday, we'll know what we want".
"Tomorrow is a long race, these guys are very quick, we had a hard night yesterday, better night today". There was smoke on Kvyat's Toro Rosso as he came into the pits, meanwhile, Verstappen had now taken the top spot. Perhaps there was a bit of time in the last sector to find but in general I am very pleased with how the vehicle and I performed. His teammate Stoffel Vandoorne is ninth and Carlos Sainz rounds out the top 10.
Davis Cup: France, Serbia level at 1-1 on day one
The other singles match, if needed, is scheduled to pit Belgium's Steve Darcis against John Millman. Arthur de Greef and Ruben Bemelmans will team up against John Peers and Jordan Thompson in doubles.
Vehicle seat checkpoint will be held in Moab this month
The study findings are scheduled for presentation on September 18 at the American Academy of Pediatrics meeting, in Chicago. While more parents are making sure their young children are protected there is a drop off when they get older.