Ryan Briscoe grabbed the fastest time in a frenetic end to Saturday morning IndyCar practice at Mid-Ohio, while his championship-leading Penske team-mate Will Power had a heavy crash.
Power was on his eighth lap of the session when he went off at Turn 1 and had a violent rearward impact with the tyre barriers. The Australian was unhurt, and the team immediately began work on rebuilding the car ready for qualifying at 12.35pm local time.
While Power's crew commenced the repair effort, his rivals were engaged in rapid-fire place-swapping at the front of the field, as the lead changed hands constantly while drivers tried qualifying set-ups late on.
Briscoe ended up on top with a 1m07.1256s, ahead of Ganassi's Dario Franchitti by just 0.0087 seconds.
A strong session for KV Racing saw EJ Viso and Mario Moraes leap to third and fourth late on, with their team-mate Takuma Sato in eighth.
Helio Castroneves (Penske) and Ryan Hunter-Reay (Andretti Autosport) completed the top six ahead of Ganassi's Scott Dixon.
Another strong road course run from Simona de Silvestro saw the HVM driver take 10th, just behind Dreyer & Reinbold's Justin Wilson. Friday pacesetter Graham Rahal (Newman/Haas) was back in 11th this morning, while Dreyer & Reinbold's debutant JR Hildebrand could not repeat his stunning Friday form but took a still highly respectable 15th.
Pos Driver Team Time Gap
1. Ryan Briscoe Penske 1m07.1256s
2. Dario Franchitti Ganassi 1m07.1343s + 0.0087s
3. EJ Viso KV 1m07.3965s + 0.2709s
4. Mario Moraes KV 1m07.4558s + 0.3302s
5. Helio Castroneves Penske 1m07.4891s + 0.3635s
6. Ryan Hunter-Reay Andretti 1m07.4907s + 0.3651s
7. Scott Dixon Ganassi 1m07.5053s + 0.3797s
8. Takuma Sato KV 1m07.5536s + 0.4280s
9. Justin Wilson Dreyer & Reinbold 1m07.6484s + 0.5228s
10. Simona de Silvestro HVM 1m07.6700s + 0.5444s
11. Graham Rahal Newman/Haas 1m07.7939s + 0.6683s
12. Tony Kanaan Andretti 1m07.7954s + 0.6698s
13. Raphael Matos De Ferran Dragon 1m07.7983s + 0.6727s
14. Bertrand Baguette Conquest 1m07.8151s + 0.6895s
15. JR Hildebrand Dreyer & Reinbold 1m07.8403s + 0.7147s
16. Marco Andretti Andretti 1m07.9092s + 0.7836s
17. Hideki Mutoh Newman/Haas 1m07.9567s + 0.8311s
18. Alex Tagliani FAZZT 1m08.0204s + 0.8948s
19. Adam Carroll AFS/Andretti 1m08.0288s + 0.9032s
20. Vitor Meira AJ Foyt 1m08.2615s + 1.1359s
21. Alex Lloyd Dale Coyne 1m08.3637s + 1.2381s
22. Dan Wheldon Panther 1m08.3708s + 1.2452s
23. Danica Patrick Andretti 1m08.3839s + 1.2583s
24. Will Power Verizon Penske 1m09.4844s + 2.3588s
25. Jay Howard Sarah Fisher 1m10.3392s + 3.2136s
26. Milka Duno Dale Coyne 1m11.6510s + 4.5254s
27. Franceso Dracone Conquest 1m12.6090s + 5.4834s