Defending champion Andretti leads after first practice session

Marco Andretti picked up where he left Iowa Speedway last year - at the front of the field.

The 2011 IZOD IndyCar Series Iowa Corn Indy 250 champion was first after the first practice session at the Newton track. Andretti recorded a fastest lap of 17.4126 seconds which translates to 184.832 miles per hour.

Rookie Josef Newgarden was second at 184.480 and Alex Tagliani was third at 184.179.

Practice times are crucial this year at Iowa Speedway. The IZOD IndyCar Series instituted heat races to race qualifying instead of two-lap, single-car qualifying. Fields of the three heat races will be determined by performances in the two practice sessions. The top eight will race in one determining the top eight starting positions for the race Saturday night at 9. The drivers in odd positions, starting at ninth and through the remainder of the field will compete for spots nine, 11, 13, 15, 17, 19, 21, 23 and 25. Drivers in even positions after practice will run in a heat for places 10, 12, 14, 16, 18, 20, 22 and 24.