Ganassi's Dario Franchitti came from nowhere in the earlier Friday practice to claim pole position with his qualifying run - and seemed as surprised as anyone that he'd pulled it off.
"That was cool," Franchitti admitted. "I didn't expect anything like that ... We didn't really have a car that had good balance, that was quick, any of those things.
"That's quite a turnaround from practice. Practice is one thing, qualifying is another - and then there is the race," added the Scot, who is aiming for a second consecutive win on the Milwaukee Mile. "I am very pleased as much as I am surprised."
His two-qualifying lap aggregate time of 43.3100s (168.737mph) was 0.1157s ahead of last week's race winner at Texas, Dale Coyne Racing's Justin Wilson.
"I feel like we've made some progress in understanding this car and what it's looking for, so we'll keep chipping away at it and making the car better and better," said Wilson. "I'm having a lot of fun. Qualifying is great, we'll just keep our heads down, keep working on it."
Wilson said that he was definitely feeling boosted by last week's success - and that he also felt a lot to prove following the team getting penalised for a technical infringement that cast a cloud on his victory.
"The confidence has helped a lot," he said. "We were very pleased with last week. Obviously there was the whole question over the legality, but that's why we've tried to come back and back it up with and we've proved that we're here and we're here to stay."
However, despite setting the second fastest time for the day, Wilson will actually outside the top ten because of a starting grid penalty for an unscheduled engine change post-Texas. Will Power, Scott Dixon, Mike Conway, Takuma Sato, Josef Newgarden and now also Ryan Briscoe all have ten-place starting grid penalties for engine changes since last week's race in Texas.
That leaves Franchitti sharing the front row of the grid with Ryan Hunter-Reay.
"We had a great run," said the Andretti Autosport driver. "The guys did a great job on the car - we were all over the sixth-gear limiter on our last lap - or I think we would have been quick enough for pole. We couldn't have predicted we would be that quick though, it's the quickest we've been all weekend."
The second row of the grid will be an all-Brazilian affair, with Rubens Barrichello a particularly welcome surprise in third place for his first-ever short oval race start.
"I am extremely happy with today's qualifying," he beamed. "As soon as we rolled the car out on track it felt good and it's a great feeling to be able to go flat. I have been to Milwaukee a few times as a spectator and tested here a couple of weeks ago, but everything felt much better today."
He'll start alongside Penske's Helio Castroneves, who posted the second-fastest single lap speed of the session (168.584mph) on his first circulation but then had to back off dramatically on the second after getting loose and hitting the engine rev limiter.
"We had a very fast first lap but the second one unfortunately I pushed too much and it lowered our two-lap average," he explained. "We are going to continue working hard so we have a good race car tomorrow and hopefully head to the front."
Qualifying utilised the traditional oval qualification format: each driver going out in a pre-set order to run one warm-up lap followed by two qualifying laps that together provide the average lap speed and total combined aggregate time. Next weekend's race at Iowa will instead trial a new 'heats' format to try livening the session up.
The third row of the grid will see Barrichello's KV Racing Technology team mates EJ Viso and Tony Kanaan lining up side-by-side, confirming impressive pace for the team as a whole on the Milwaukee Mile.
"The performance we have shown at this track up to now has been strong," said an excited Viso. "What makes me even more excited is that I feel we have a good race car. There are going to be a lot of cars dropping back in this race because the hot weather temperatures will have a big effect. Hopefully, our strategy and the car development we have done will take us to the front and we can stay there."
"Tomorrow will be an interesting day and hopefully we can bring a home a good result," added Kanaan.
Simon Pagenaud will start in seventh place for Schmidt-Hamilton alongside Andretti's James Hinchcliffe. The French sportscar driver felt that his car hadn't yet shown its full potential despite the top ten qualifying position.
"The car still has something left in it," he said. "I really enjoyed the qualifying here today. It's one of those deals where you have to be flat to be on pole, and that's very challenging to do here. It's such an adrenaline rush to qualify here."
"It's good to see the job the guys are doing," the series rookie added. "They know what I need to feel comfortable on the ovals. I'm learning, learning quick, but still learning every day."
Hinchcliffe meanwhile was more relieved with his qualifying showing after a less than straightforward day or it. "We didn't roll off this morning with a great car, but we've been working away at it and we definitely have it better now than it was this morning," he said.
"I'm pleased with how it went, I just wish we would've had more of a head start on that going in," he added. "The first lap would've been stronger if I had known then what I know now, and did what I did on the second lap. It's alright as long as we have a good race car, then we'll be able to move up quickly in the race."
Marco Andretti and JR Hildebrand round out the top ten, with Graham Rahal lining up in 11th place for the start ahead of the first of those cars to have been hit by a grid penalty, Justin Wilson in 12th.
Wilson's Dale Coyne team mate James Jakes had featured strongly in practice but performed poorly in qualifying, finishing in 20th position in the timings but subsequently boosted to 16th on the grid by all those penalties.
"Our qualifying position is disappointing because we had a really good car," admitted the Leeds-born driver. "Practices were great. I wish would could have had another run for qualifying but right now I'm just looking ahead to tomorrow and bringing the Boy Scouts of America Honda back up front."
Oriol Servia also had a surprisingly poor time of it in qualifying, which he admitted the Panther/DRR team needed to look into overnight. "For some reason this morning we didn't get the setup right, or there is something wrong with the car that we aren't understanding. In qualifying, the car felt its best, it was just very slow," he said.
Britain's Mike Conway was the slowest man in qualifying as well as having one of the starting grid penalties, and will therefore start the AJ Foyt Racing car from dead last.
"It's a pretty tough little place," he said of the Milwaukee Mile short oval. "It's not easy to go flat all the way around. The car's pretty on edge if you try to get a fast lap but we'll see what it's like."
The race is due to start at noon local time, 6pm BST and is shown live in the UK on Sky Sports
Full qualifying times
as well as times from the earlier practice 1
and practice 2
sessions are available.Starting grid
1. #10 Dario Franchitti
2. #28 Ryan Hunter-Reay
3. #8 Rubens Barrichello
4. #3 Helio Castroneves
5. #5 EJ Viso
6. #11 Tony Kanaan
7. #77 Simon Pagenaud
8. #27 James Hinchcliffe
9. #26 Marco Andretti
10. #4 JR Hildebrand
11. #38 Graham Rahal
12. #18 Justin Wilson
13. #98 Alex Tagliani
14. #12 Will Power
15. #6 Katherine Legge
16. #19 James Jakes
17. #67 Josef Newgarden
18. #83 Charlie Kimball
19. #2 Ryan Briscoe
20. #22 Oriol Servia
21. #9 Scott Dixon
22. #20 Ed Carpenter
23. #78 Simona de Silvestro
24. #15 Takuma Sato
25. #14 Mike Conway
(H) ** denotes ten-place grid penalty applied(H)=Honda, (C)=Chevrolet, (L)=Lotus