It was a nice dry Saturday at Detroit Belle Isle for the drivers to have one final hour's practice in the morning before qualifying got underway later in the afternoon, but conditions were still a lot breezier and chillier than they had been accustomed to just a week ago in the blistering sunshine of Indianapolis.
The session had barely got underway when there was a quick red flag for a spin by Ryan Briscoe on his out lap, and the 2.07-mile, 14-turn street course had only just reopened when Oriol Servia then spun and went into the wall at turn 14 with a heavy impact that badly damaged the right-front of the Panther/DRR car.
Emphasising how much everyone was really pushing things close to the limit on this unfamiliar circuit, Dario Franchitti was next to spin five minutes into the next green session just before the midpoint of the one hour practice session. He lost the #10 car at turn 5, but mercifully in his case kept the car off the barriers.
After Franchitti's mishap, there was a finally a decent period of green flag running for the remainder of the session, which survived a brief bit of off-roading for Helio Castroneves out of turn 12, Ed Carpenter taking to the run-off area at turn 8 with around six minutes remaining, and a harmless spin by Justin Wilson that he was able to deal with without assistance.
Off the track in pit lane, there was also some wheel-to-wheel contact between the two Ryans in the field when Ryan Hunter-Reay was ushered out of his pit box right into the path of Penske's Ryan Briscoe who was also exiting the pits and returning to the track. No serious harm was done, but Hunter-Reay was given a 60 second stop-and-hold penalty for the unsafe pit release.
During this time, Scott Dixon had gone top of the timesheets with a lap of 1:11.3913, over a quarter of a second faster than Will Power who had a similar margin over Hunter-Reay. Both drivers at the front would shave a little more time off with their last flying laps of the morning.
In total, there were seven Chevrolet cars in the top ten - including all three Penske cars - and just three Hondas, with Dixon joined by Justin Wilson and Simon Pagenaud. Graham Rahal briefly nudged his way into the top ten in the final minutes, but was summarily hustled out again by Tony Kanaan and JR Hildebrand before the chequered flag came out to end proceedings.
Qualifying for the Chevrolet Detroit Belle Isle Grand Prix takes place at 11.45am (4.45pm BST). After the unique format seen at Indianapolis, qualifying reverts to the usual road/street system with two groups having 15 minutes to set a time, and the top six from each group moving forward into a single ten minute Top 12 session. The top six from this round fight it out for pole in the Firestone Fast Six to complete the grid order.
The race itself is scheduled to take place on Sunday afternoon at 3.45pm (8.45pm BST) after a final early morning half-hour warm-up opportunity.
Full practice 3 times