Castroneves on top as Indy opens

Under the truncated 2010 schedule, the opening day started with two hours for experienced drivers, before the remainder of the afternoon was given over to rookies and drivers eligible for 'refresher' testing.

It was Ganassi duo Dario Franchitti and Scott Dixon who set the early pace, and started producing laps in excess of 226mph - almost 2mph above the 2009 pole speed - almost immediately.

That looked set to keep them comfortably on top of the timing screens, until Penske driver Castroneves averaged 226.603mph on a late lap.

Dan Wheldon showed good early form for Panther Racing in fourth, ahead of Tony Kanaan. The Brazilian had a busy afternoon - shaking down the cars of his Andretti Autosport team-mates Ryan Hunter-Reay, Danica Patrick, Marco Andretti and John Andretti to establish a baseline for all five entries before getting his own programme underway.

The 12 drivers in the rookie and refresher category now have the track to themselves until 6pm local time. Sunday's practice follows the same format, before the full field takes to the track together on Monday.

Pos  Driver             Team               Time      Gap
 1.  Helio Castroneves  Penske             39.7170s
 2.  Dario Franchitti   Ganassi            39.7290s  + 0.0120s
 3.  Scott Dixon        Ganassi            39.7813s  + 0.0643s
 4.  Dan Wheldon        Panther            39.8921s  + 0.1751s
 5.  Tony Kanaan        Andretti           40.0369s  + 0.3199s
 6.  Ed Carpenter       Panther/Vision     40.0726s  + 0.3556s
 7.  Marco Andretti     Andretti           40.0952s  + 0.3782s
 8.  Ryan Briscoe       Penske             40.1098s  + 0.3928s
 9.  John Andretti      Andretti           40.1206s  + 0.4036s
10.  Will Power         Penske             40.1251s  + 0.4081s
11.  Mario Moraes       KV                 40.1906s  + 0.4736s
12.  Hideki Mutoh       Newman/Haas        40.1959s  + 0.4789s
13.  Danica Patrick     Andretti           40.2412s  + 0.5242s
14.  Vitor Meira        Foyt               40.3248s  + 0.6078s
15.  Raphael Matos      de Ferran Dragon   40.3844s  + 0.6674s
16.  EJ Viso            KV                 40.4196s  + 0.7026s
17.  Sarah Fisher       Sarah Fisher       40.4703s  + 0.7533s
18.  Milka Duno         Dale Coyne         40.5314s  + 0.8144s
19.  Ryan Hunter-Reay   Andretti           40.5942s  + 0.8772s
20.  Mike Conway        Dreyer & Reinbold  40.6317s  + 0.9147s
21.  Alex Lloyd         Dale Coyne         40.6612s  + 0.9442s
22.  Justin Wilson      Dreyer & Reinbold  40.7143s  + 0.9973s
23.  Paul Tracy         KV                 40.9996s  + 1.2826s