Colton Herta has become the youngest ever IndyCar pole-sitter while Will Power will start third in the 10th race of the season, at Road America.
Scott Dixon, however, failed to turn a lap in the second phase of qualifying after a mechanical issue beset his #9 Chip Ganassi Honda at the end of his first hit-out.
Herta clocked a 1:42.9920s in the #88 Harding Steinbrenner Racing Honda which put him 0.1773s clear of Alexander Rossi (#27 Andretti Autosport Honda).
Power (#12 Chevrolet) will be joined on the second row of the grid by Team Penske team-mate and series leader, Josef Newgarden (#2 Chevrolet).
Row 3 is an all-Rahal Letterman Lanigan affair with Graham Rahal (#15 Honda) edging Takuma Sato (#30 Honda) in the Fast Six.
While Dixon took 12th somewhat by default, team-mate Felix Rosenqvist (#10 Honda) went out at the first time of asking and will start 18th.
Ryan Hunter-Reay (#28 Andretti Autosport Honda) and Simon Pagenaud (#22 Team Penske Chevrolet) are only slightly better off with each putting in untidy laps on their way to 15th and 16th respectively.
The 55-lap race gets underway tomorrow at 0245 AEST.
Starting grid: Road America
Pos | Num | Driver | C/E/T | Time | Session |
1 | 88 | Colton Herta (R) | D/H/F | 1:42.9920 | Fast Six |
2 | 27 | Alexander Rossi | D/H/F | 1:43.1693 | Fast Six |
3 | 12 | Will Power | D/C/F | 1:43.3749 | Fast Six |
4 | 2 | Josef Newgarden | D/C/F | 1:43.6036 | Fast Six |
5 | 15 | Graham Rahal | D/H/F | 1:43.8076 | Fast Six |
6 | 30 | Takuma Sato | D/H/F | 1:43.8790 | Fast Six |
7 | 18 | Sebastien Bourdais | D/H/F | 1:43.2989 | Top 12 |
8 | 21 | Spencer Pigot | D/C/F | 1:43.3083 | Top 12 |
9 | 5 | James Hinchcliffe | D/H/F | 1:43.3814 | Top 12 |
10 | 98 | Marco Andretti | D/H/F | 1:43.3945 | Top 12 |
11 | 20 | Ed Jones | D/C/F | 1:43.5162 | Top 12 |
12 | 9 | Scott Dixon | D/H/F | No Time | Top 12 |
13 | 31 | Patricio O’Ward (R) | D/C/F | 1:43.6061 | Group 1 |
14 | 26 | Zach Veach | D/H/F | 1:43.4488 | Group 2 |
15 | 28 | Ryan Hunter-Reay | D/H/F | 1:43.6980 | Group 1 |
16 | 22 | Simon Pagenaud | D/C/F | 1:43.4764 | Group 2 |
17 | 7 | Marcus Ericsson (R) | D/H/F | 1:43.8913 | Group 1 |
18 | 10 | Felix Rosenqvist (R) | D/H/F | 1:43.5038 | Group 2 |
19 | 60 | Jack Harvey | D/H/F | 1:44.6179 | Group 1 |
20 | 4 | Matheus Leist | D/C/F | 1:43.8570 | Group 2 |
21 | 19 | Santino Ferrucci (R) | D/H/F | 1:49.3060 | Group 1 |
22 | 59 | Max Chilton | D/C/F | 1:43.8745 | Group 2 |
23 | 14 | Tony Kanaan | D/C/F | 1:44.4183 | Group 2 |
(C)hassis: D=Dallara | (E)ngine: C=Chevy, H=Honda | (T)yre: F=Firestone