IndyCar Series championship leader Ryan Briscoe stretched his advantage to five points by leading an all-Penske front row at Chicagoland.
His team-mate Helio Castroneves will start second in Saturday night's race, ahead of Briscoe's main title rival Dario Franchitti (Ganassi).
The session was delayed by both morning rain and incidents in the preceding stock car practice, and was interrupted again halfway through by brief drizzle.
Briscoe was one of the final drivers to qualify, and was able to beat Castroneves' time and take pole with an average speed of 215.364mph over four laps.
"The car was great, and at this point we'll take any point that we can get," said the Australian. "I think it helps being at the back of the line, and getting a bit of a read from Helio. He put in four great laps and I was happy to do a little bit better."
Castroneves said he was just relieved to have a straightforward qualifying session at a track where a year ago he had been demoted from the front row to the back for illegally crossing the white line on the backstraight during his run.
"I made sure that I did not touch the white line," Castroneves joked. "I made sure I could go as close as I could without doing anything wrong."
Franchitti had held provisional pole for much of the session before the Penske duo moved ahead. He will share row two with Andretti Green's top qualifier Tony Kanaan.
Scott Dixon only managed sixth in the second Ganassi car, despite having been fastest in morning practice - when he admitted he was aided by a tow "from about eight cars."
Newman/Haas/Lanigan had a strong qualifying session, with Graham Rahal taking fifth on the grid and Oriol Servia lining up ninth, his best result since returning to the series. By contrast Robert Doornbos, whose move to HVM allowed Servia to rejoin N/H/L, was only 22nd as his team struggled in oval trim.
Pos Driver Team Speed 1. Ryan Briscoe Penske 215.364mph 2. Helio Castroneves Penske 215.202mph 3. Dario Franchitti Ganassi 214.973mph 4. Tony Kanaan Andretti Green 214.661mph 5. Graham Rahal Newman/Haas/Lanigan 214.556mph 6. Scott Dixon Ganassi 214.494mph 7. Marco Andretti Andretti Green 214.428mph 8. Mario Moraes KV 214.331mph 9. Oriol Servia Newman/Haas/Lanigan 214.126mph 10. Danica Patrick Andretti Green 214.104mph 11. Dan Wheldon Panther 213.808mph 12. Ed Carpenter Vision 213.331mph 13. Hideki Mutoh Andretti Green 213.256mph 14. Tomas Scheckter Dreyer & Reinbold 213.218mph 15. Justin Wilson Coyne 213.011mph 16. Mike Conway Dreyer & Reinbold 212.671mph 17. Raphael Matos Luczo Dragon 212.387mph 18. Ryan Hunter-Reay Foyt 212.337mph 19. Sarah Fisher Fisher 212.125mph 20. EJ Viso HVM 211.586mph 21. Milka Duno Dreyer & Reinbold 211.465mph 22. Robert Doornbos HVM 211.169mph 23. Jaques Lazier 3G 208.333mph