Colton Herta topped IndyCar practice at Mid-Ohio for Harding Steinbrenner Racing, while championship leader Josef Newgarden crashed.
In the second session, Newgarden was lying 11th fastest when he headed out on Firestone red tyres, but when he dropped a wheel off the curb exiting Turn 9, the car spun through 180-degrees and went backwards the tyre wall on the corner exit.
The red flags flew, with Newgarden given a five-minute penalty for causing them, which ended a session that restarted with less than two minutes to go.
That allowed the drivers just one final crack at a setting representative time, but with most cars tripping over each other in the traffic there were no improvements.
Herta's 1m05.729 second lap of the 2.258-mile roadcourse - a 123.671mph lap - therefore held firm in first place.
He ended up over 0.2s ahead of his nearest rivals and was almost 0.3s clear of the fastest of his Andretti team-mates - Ryan Hunter-Reay, who was fifth.
Simon Pagenaud was second fastest for Penske, pipping his team-mate Will Power, who set his fastest time on the primary tyre and was fastest on that harder compound.
Felix Rosenqvist was the top Chip Ganassi Racing driver in fourth, while James Hinchcliffe was again fast in his Arrow Schmidt Peterson Motorsports-run car to take sixth.
Matheus Leist's taking seventh for AJ Foyt Racing was a surprise boost for the beleaguered team, as he finished ahead of Jack Harvey.
Alexander Rossi appeared to be struggling with the handling of his car and languished in 13th in FP2, just ahead of his team-mate Zach Veach.
RC Enerson finished the session in 15th for Carlin, just in front of his team-mate Max Chilton.
Enerson, returning to IndyCar for the first time in three years, caused a minor fracas at the end of the session when he barged his way ahead of drivers who were trying to make a gap to try for one last flying effort.
This was put down to him simply not knowing the new-for-2019 rule that means so long as they emerge from the pitlane within 40s of the restart following a late red flag in practice, drivers are guaranteed an out-lap and a flying lap.
In FP1, Scott Dixon topped the order with a time of 1m06.097s for Ganassi.
He ended up 0.148s ahead of Spencer Pigot (Ed Carpenter Racing), who out Pagenaud and Newgarden
|1||Colton Herta||Harding Racing||1m05.7292s||16|
|2||Simon Pagenaud||Team Penske||0.2021s||15|
|3||Will Power||Team Penske||0.2643s||16|
|4||Felix Rosenqvist||Chip Ganassi Racing||0.2926s||24|
|5||Ryan Hunter-Reay||Andretti Autosport||0.2994s||13|
|6||James Hinchcliffe||Schmidt Peterson Motorsports||0.3026s||14|
|7||Matheus Leist||AJ Foyt Enterprises||0.4335s||15|
|8||Jack Harvey||Meyer Shank Racing||0.5188s||19|
|9||Spencer Pigot||Ed Carpenter Racing||0.6199s||15|
|10||Sebastien Bourdais||Dale Coyne Racing||0.7074s||16|
|11||Josef Newgarden||Team Penske||0.8415s||14|
|12||Marcus Ericsson||Schmidt Peterson Motorsports||0.8473s||13|
|13||Alexander Rossi||Andretti Autosport||0.8514s||13|
|14||Zach Veach||Andretti Autosport||0.9218s||18|
|16||Scott Dixon||Chip Ganassi Racing||1.0103s||16|
|17||Santino Ferrucci||Dale Coyne Racing||1.0231s||14|
|19||Tony Kanaan||AJ Foyt Enterprises||1.1749s||14|
|20||Takuma Sato||Rahal Letterman Lanigan||1.2244s||15|
|21||Ed Jones||Ed Carpenter Racing||1.2358s||16|
|22||Marco Andretti||Andretti Herta||1.3848s||14|
|23||Graham Rahal||Rahal Letterman Lanigan||1.5463s||15|
|1||Scott Dixon||Chip Ganassi Racing||1m06.0973s||13|
|2||Spencer Pigot||Ed Carpenter Racing||0.1482s||14|
|3||Simon Pagenaud||Team Penske||0.1692s||16|
|4||Josef Newgarden||Team Penske||0.2091s||15|
|5||James Hinchcliffe||Schmidt Peterson Motorsports||0.2638s||14|
|6||Ryan Hunter-Reay||Andretti Autosport||0.3521s||14|
|7||Will Power||Team Penske||0.4868s||18|
|8||Felix Rosenqvist||Chip Ganassi Racing||0.5077s||24|
|9||Sebastien Bourdais||Dale Coyne Racing||0.6422s||13|
|11||Jack Harvey||Meyer Shank Racing||0.9387s||13|
|12||Colton Herta||Harding Racing||0.9528s||18|
|13||Alexander Rossi||Andretti Autosport||1.0070s||15|
|14||Takuma Sato||Rahal Letterman Lanigan||1.0499s||14|
|15||Marco Andretti||Andretti Herta||1.1623s||15|
|16||Ed Jones||Ed Carpenter Racing||1.2001s||14|
|17||Graham Rahal||Rahal Letterman Lanigan||1.2311s||13|
|18||Marcus Ericsson||Schmidt Peterson Motorsports||1.2336s||21|
|19||Matheus Leist||AJ Foyt Enterprises||1.2703s||16|
|20||Santino Ferrucci||Dale Coyne Racing||1.3222s||17|
|22||Zach Veach||Andretti Autosport||1.7457s||15|
|23||Tony Kanaan||AJ Foyt Enterprises||1.8458s||13|