Ed Carpenter opened the 2013 Indianapolis 500 by going fastest on the first day of practice on Saturday.
The owner/driver's 220.970mph lap was just 0.05mph quicker than second-fastest Josef Newgarden's effort for Sarah Fisher Hartman, with Andretti rookie Carlos Munoz claiming the third-best time.
Sixteen car/driver combinations took to the track during the day, with Ganassi pair Scott Dixon and Dario Franchitti running in both their race and spare cars, and Helio Castroneves turning some laps in AJ Allmendinger's Penske Dallara-Chevrolet before handing it over to the American.
"The biggest thing for me, and you hear everybody tell you, [was that] you can't let your guard down around here," said event rookie Allmendinger, who ended the day eigth-fastest.
"Just because for four laps in a row you went wide open, you think, 'OK, I've got this'. You can't relax.
"A couple of times down the back straightaway, I kind of caught myself.
"It's just the way this place is; that's what makes it so special. You have got to give it its respect every lap.
"Not just when you show up. Not just in qualifying. Not just in the race. Every lap you have got to show respect."
Allmendinger, Munoz and Tristan Vautier also completed their rookie orientation programmes during the day.
Conor Daly, who will attempt to make his Indy 500 debut with AJ Foyt Racing, was at Barcelona racing in GP3 and is expected to do his rookie orientation runs on Monday.
Pos Driver Team Engine Mph Time Gap 1. Ed Carpenter Carpenter Chevy 220.970 40.7296s 2. Josef Newgarden Fisher Honda 220.920 40.7387s + 0.0091s 3. Carlos Munoz Andretti Chevy 220.720 40.7756s + 0.0460s 4. Charlie Kimball Ganassi Honda 220.633 40.7917s + 0.0621s 5. Alex Tagliani Herta Honda 220.248 40.8631s + 0.1335s 6. Dario Franchitti Ganassi Honda 219.873 40.9328s + 0.2032s 7. Tony Kanaan KV Chevy 219.125 41.0725s + 0.3429s 8. AJ Allmendinger Penske Chevy 218.967 41.1020s + 0.3724s 9. Scott Dixon Ganassi Honda 218.214 41.2439s + 0.5143s 10. Helio Castroneves Penske Chevy 217.923 41.2990s + 0.5694s 11. Takuma Sato Rahal Honda 217.734 41.3348s + 0.6052s 12. Will Power Penske Chevy 217.595 41.3612s + 0.6316s 13. Simona de Silvestro KV Chevy 216.938 41.4866s + 0.7570s All cars Dallara DW12
When drivers used two cars, only their fastest time listed