Canada's James Hinchcliffe turned the fastest lap Wednesday in the opening Indianapolis 500 practice session while season points leader Scott Dixon was third and Spain's Fernando Alonso was fifth.
Hinchcliffe, who sustained serious injuries in a 2015 Indy 500 practice crash only to capture pole position in 2016, circled the famed 2 1/2-mile (4km) oval in 40.0844 seconds at an average speed of 224.526 mph (361.339 km/hr) in a Honda-powered Dallara.
"Luckily, not a ton of surprises," Hinchcliffe said. "Everybody at Andretti Autosport has worked their tails off to prepare for this race.
"It's just practice. There's obviously a long way to go. But whenever you can kick off the month strong and know you’ve got a decent package, you can kind of work on it from there. It makes your sleep a little better now and between the race."
The annual oval classic at Indianapolis Motor Speedway was postponed from May 24 to August 23 by the COVID-19 pandemic and will be raced without spectators.
Practice will continue through Friday with qualifying on Saturday and Sunday to fill the grid for the 33-car field.
Marco Andretti, Hinchcliffe's American teammate, was second on 224.345 while New Zealand's Dixon was third on 224.047 and another Andretti racer, American Ryan Hunter-Reay, was fourth on 223.341.
Dixon has won three races in a season shortened by COVID-19 to seize the points lead as he chases a sixth career IndyCar season crown. The 40-year-old Kiwi won his only Indy 500 in 2008 but has reached the podium three other times.
Two-time Formula One world champion Alonso was fifth on 223.238 mph as he tries to complete the Triple Crown of motor racing by adding an Indy 500 trophy to his wins at the 24 Hours of Le Mans and the F1 Monaco Grand Prix -- a treble only England's Graham Hill has ever completed.
Alonso started fifth and led 24 laps before engine failure left him 24th. He failed in a bid to qualify for last year's Indy 500.