Penske's Will Power was on blistering form on Saturday afternoon at Pocono Raceway, setting an unofficial new track record speed of 223.348mph (40.2959s) on the 2.5-mile 'tri-oval' circuit.
In fact no fewer than 11 drivers were already faster than last year's two-lap qualifying average speed of 221.273mph recorded by Marco Andretti, with Power just a slender 0.0615s ahead of Andretti Autosport's Carlos Munoz. The top 11 were covered by 0.3617s and 19 drivers were within a second of Power's time in the hou-long afternoon session. All of the fastest laps were set with the help of a 'tow' or aerodynaic assist from running close behind other cars.
Earlier in the day, Ganassi's Tony Kanaan had paced the first practice session with a lap of 221.344mph (40.6607s) five minutes before the chequered flag putting him just ahead of a trio of Andretti Autosport cars consisting of Ryan Hunter-Reay, Andretti Autosport and James Hinchcliffe. Kanaan subsequently improved his lap to 222.528mph (40.4444s) to maintain third place in the combined practice standings just ahead of Rahal Letterman Lanigan Racing's Graham Rahal.
There was an even split of five entries apiece between the Chevrolet and Honda stables for the two sessions, which saw a total of 1482 laps run as teams worked to complete the required mileage per engine that would means that they would be allowed to swap out the unit for a new one without penalty.
The morning session was incident-free with just two cautions to clear up debris. Hunter-Reay's participation was delayed by the discovery of a punctured radiator which saw him lose a third of the available running time, but he was quickly up to speed once he got out on the track.
By contrast the afternoon session saw a prolonged 13-minute yellow flag stoppage after Jack Hawksworth had a hard impact into turn 1 in the Bryan Herta Autosport #98 car. Hawksworth was able to climb out but appeared to be limping, and it was confirmed that he'd banged his knee in the impact.
"I'm sore, but I feel all right," he said after being evaluated and released by the in-field care centre.
"We'd been understeering in turn 1 during the whole session and there's a tailwind going into there so we'd been pushing a lot," he explained. "We just put tyres on and went into 1 and picked up a big oversteer instead of the understeer and it took us out. If I thought I was going to stick it into the wall, I would have thought it would be on turn 3, but it was turn 1."
While Hawksworth was cleared to race, the problem now is rebuilding the heavily damaged car. It seems likely that the team will have to spit out qualifying, which takes place at 5pm local time (10pm BST). Ironically the team had the same experience of wiping out the primary race chassis when they competed here last year with Alex Tagliani at the wheel.
That strong tailwind going into turn 1 had been giving all the drivers something of a headache all day: "It makes it a little tough to set up, especially when you are going from one corner to another, even though it is an oval," Helio Castroneves explained.
"When it's a constant wind, it's not a problem. When it's a gust of wind, that's when it's a problem. On one lap, the car is one way and the next one is, 'Whoa, what happened?' The inconsistency is what makes it difficult for us."
There were also problems for Ganassi's Ryan Briscoe, who lost a lot of time to an ECU issue, while Justin Wilson suffered a late electrical problem on the Dale Coyne Racing car that truncated his track time.
Full practice 1 results
Full practice 2 results
Full combined practice results