Ed Carpenter took a step towards a second consecutive Indianapolis 500 pole after setting the top speed on Saturday's opening day of qualifying.
Carpenter was the only driver to break a 230mph average in practice on Friday, and he followed it up with a 230.661mph four-lap average 24 hours later.
His time came after he waved off an earlier 230.114mph effort, and left him optimistic about his chances of pole.
"It's just got to go like it did last year, we've got to get it right for that one run," he said.
"Everybody's got one shot at it, and I think you saw guys going faster, going slower, going faster, going slower today depending on which run they were on. Some guys moved forward, some guys moved back when they pulled out a time.
"It just comes down to the engineers and the drivers making the right decision, believing in it and going out a laying down four good ones."
Joining Carpenter in the Fast Nine shootout for the first three rows on the grid will be Carlos Munoz, who qualified second last year, Helio Castroneves, James Hinchcliffe, Will Power, Marco Andretti, Simon Pagenaud, Josef Newgarden and JR Hildebrand.
Newgarden's presence in the top nine was one of the day's surprises, and the American admitted that even he had not expected to do so well.
"We definitely went for it," he said. "It wasn't quite good enough to be at the top, but somehow we snuck in. It's pretty cool - a really good job by that team. Sometimes it's just fast and you don't know why. There are little tweaks, though.
"Scrubbing, I think, was a big deal today. Once we started trimming to a certain point we just started getting too much scrub. We figured out a way to limit that and I think that was the difference for us.
"It's a funny place. Sometimes you get the conditions right or just the right run, but it definitely seems to pick you. When this place wants you to be fast, it lets you be fast."
Kurt Busch was in contention for a top nine spot right up to the point that he left the track at 3pm to fly to Charlotte to prepare for the NASCAR All-Star race, but other drivers took advantage of the remaining time to improve their speeds and bump the Andretti driver down to 10th.
"I've qualified Pro Stocks on the quarter-mile; I've done the longest track on the NASCAR circuit [Talladega] but to do four laps here on a 2.5-mile track, that's a 10-mile run," he said.
"That's the longest I've had to focus for a qualifying run. Those four laps felt like one; 230 is a totally different game. I wasn't as focused as I needed to be; the moment of Indy can kind of overtake you. It was a very solid run; I was hoping for more."
Among the notable absentees from the pole battle is Ganassi, with all five of its cars falling in between 15th and 23rd-fastest.
Pos Driver Team/Engine Speed 1. Ed Carpenter Carpenter/Chevy 230.661 2. Carlos Munoz Andretti/Honda 230.460 3. Helio Castroneves Penske/Chevy 230.432 4. James Hinchcliffe Andretti/Honda 230.407 5. Will Power Penske/Chevy 230.323 6. Marco Andretti Andretti/Honda 230.134 7. Simon Pagenaud Schmidt/Honda 230.070 8. Josef Newgarden Fisher/Honda 230.033 9. JR Hildebrand Carpenter/Chevy 230.027 10. Kurt Busch Andretti/Honda 229.960 11. Ryan Hunter-Reay Andretti/Honda 229.899 12. Jack Hawksworth Herta/Honda 229.816 13. Juan Pablo Montoya Penske/Chevy 229.785 14. Justin Wilson Coyne/Honda 229.618 15. Scott Dixon Ganassi/Chevy 229.283 16. Mikhail Aleshin Schmidt/Honda 229.091 17. Ryan Briscoe Ganassi/Chevy 228.825 18. Takuma Sato Foyt/Honda 228.786 19. Charlie Kimball Ganassi/Chevy 228.710 20. Graham Rahal Rahal/Honda 228.664 21. Sage Karam Ganassi/Chevy 228.650 22. Townsend Bell KV/Chevy 228.508 23. Tony Kanaan Ganassi/Chevy 228.435 24. Sebastien Bourdais KV/Chevy 228.388 25. Pippa Mann Coyne/Honda 228.358 26. Sebastian Saavedra KV/Chevy 228.294 27. Jacques Villeneuve Schmidt/Honda 228.171 28. James Davison KV/Chevy 228.150 29. Oriol Servia Rahal/Honda 228.034 30. Carlos Huertas Coyne/Honda 227.991 31. Alex Tagliani Fisher/Honda 227.813 32. Martin Plowman Foyt/Honda 227.043 33. Buddy Lazier Lazier/Chevy 226.543 Speeds are average over four-lap run All drivers use Dallara chassis