A pre-session downpour and high winds delayed the session by more than eight hours and when it did run for 60 minutes, Newgarden lapped the 1.25-mile oval, formerly known as Gateway, in 24.9944s at 180.040mph.
It also marked the debut of Firestone’s softer alternate tyre on an oval, with teams mandated to run it in this session. Teams started on the primaries and most switched to the red-walled alternates towards the second half of the session.
Marcus Ericsson set the early pace at 25.3202s, a speed of 177.724mph in his Honda-powered Chip Ganassi Racing entry, before he was toppled by future team-mate Colton Herta’s Andretti Autosport machine with 25.2607s at 178.142mph.
This year’s oval dominator Josef Newgarden, a four-time winner here, then took P1 for Team Penske with 24.9944s at 190.040mph after 15 minutes of running, 0.2425s ahead of Alexander Rossi’s Arrow McLaren car at 178.310mph.
Rossi was the first to try the alternates with 37 minutes of the session remaining but didn’t improve his fastest time as he embarked on a race simulation to evaluate degradation – and ran for 33 laps. His McLaren team-mate Felix Rosenqvist jumped up to second on primaries on 25.2076s at 178.518mph, before Penske’s Scott McLaughlin beat that with 25.0902s at 179.353mph.
Takuma Sato (Ganassi) and Will Power (Penske) moved up to third and fourth respectively, while Herta had a huge moment at Turn 4 on alternates but just kept it out of the wall.
The caution flag flew with 10 minutes remaining as Sato ran wide in Turn 4, although he insisted that he didn’t touch the wall.
The restart didn’t last for long, as McLaughlin spun into the grass on the inside of Turn 2, Power hit the wall in avoidance and spun, and then Ericsson collected him at high speed.
Newgarden ended the hour almost a tenth clear of McLaughlin, Sato, Power, Rosenqvist and Rossi. There will now be a ‘high-line’ practice session at 9pm ET, for cars to lay rubber in an attempt to improve Sunday’s racing.
IndyCar officials have also announced nine-position starting grid penalties for Scott McLaughlin (Penske), Scott Dixon and Takuma Sato (Ganassi), Kyle Kirkwood (Andretti) and Agustin Canapino (Juncos Hollinger Racing) for unapproved engine changes (ie: taking a fifth powerplant) since the last round on the Indianapolis Motor Speedway road course.