Justin Wilson set the fastest time in the second IndyCar practice session at Milwaukee.
The Dale Coyne Racing driver, who won last weekend's race at Texas, topped the sheets with a 164.785mph (22.1744s) lap of the one-mile oval, giving him the edge over Sarah Fisher Hartman's Josef Newgarden (164.140mph).
Helio Castroneves was third fastest and best of the Chevrolet-powered drivers with his 163.927mph effort, with KV's EJ Viso and Ganassi's Graham Rahal completing the top five.
Reigning champion Will Power, who join Wilson in being one of several drivers carrying 10-place grid penalties into the weekend, was 13th fastest, while 2011 Milwaukee winner Dario Franchitti had to settle for 18th spot.
Pos Driver Team/Car Time Gap
1. Justin Wilson Coyne DW12-Honda 22.1744s
2. Josef Newgarden Fisher DW12-Honda 22.2438s + 0.0694s
3. Helio Castroneves Penske DW12-Chevy 22.2904s + 0.1160s
4. EJ Viso KV DW12-Chevy 22.3664s + 0.1920s
5. Graham Rahal Ganassi DW12-Honda 22.3719s + 0.1975s
6. Rubens Barrichello KV DW12-Chevy 22.4185s + 0.2441s
7. James Hinchcliffe Andretti DW12-Chevy 22.4360s + 0.2616s
8. JR Hildebrand Panther DW12-Chevy 22.4603s + 0.2859s
9. Scott Dixon Ganassi DW12-Honda 22.4781s + 0.3037s
10. Ryan Hunter-Reay Andretti DW12-Chevy 22.4841s + 0.3097s
11. Takuma Sato Rahal DW12-Honda 22.5021s + 0.3277s
12. James Jakes Coyne DW12-Honda 22.5361s + 0.3617s
13. Will Power Penske DW12-Chevy 22.6051s + 0.4307s
14. Alex Tagliani Herta DW12-Honda 22.6203s + 0.4459s
15. Tony Kanaan KV DW12-Chevy 22.7542s + 0.5798s
16. Ryan Briscoe Penske DW12-Chevy 22.7592s + 0.5848s
17. Simon Pagenaud Schmidt DW12-Honda 22.7706s + 0.5962s
18. Dario Franchitti Ganassi DW12-Honda 22.8212s + 0.6468s
19. Marco Andretti Andretti DW12-Chevy 22.9933s + 0.8189s
20. Charlie Kimball Ganassi DW12-Honda 23.0157s + 0.8413s
21. Ed Carpenter Carpenter DW12-Chevy 23.1076s + 0.9332s
22. Mike Conway Foyt DW12-Honda 23.1286s + 0.9542s
23. Katherine Legge Dragon DW12-Chevy 23.2729s + 1.0985s
24. Oriol Servia Panther/DRR DW12-Chevy 23.3180s + 1.1436s
25. Simona de Silvestro HVM DW12-Lotus 23.3261s + 1.1517s