Indianapolis ? Sam Hornish Jr. is determined not to make any mistakes in his third Indianapolis 500.

Hornish, the defending Indy Racing League champion and its current points leader, has been a force at most tracks since arriving on the Indy-car scene but not at the Indianapolis Motor Speedway.

Sam Hornish Jr. straps on his helmet. Hornish and the rest of the Indianapolis 500 field took part in a final practice session Thursday at Indianapolis Motor Speedway.

He made his debut as a precocious 20-year-old in 2000 and finished 24th, crashing out of the race after 153 of 200 laps.

Last year, Hornish embarrassed himself by spinning on cold tires on a restart 18 laps into the 500. He flattened all four tires, lost four laps in the pits and wound up 14th.

He can’t wait for Sunday.

“We’re really excited about the race,” he said Thursday after his lap of 225.279 mph placed him second to Tony Kanaan’s 225.752 as all 33 starters made it onto the 21/2-mile oval for the traditional “Carburetion Day,” the only practice in the week between the end of qualifying and the start of the race.

“You just have to try and come back to it and see if you can do a better job,” Hornish said. “Last year, I made a mistake and I’m going to try to limit the problems this time.

Members of Helio Castroneves' pit crew react as he speeds away. Castroneves defeated Jeff Ward in the finals of the pit stop competition Thursday at Indianapolis.

“The whole month we’ve been trying to take things easy and do things logically and not get ahead of ourselves and not peak until race day. … It’s hard to maintain your focus for the whole month.”

Nobody in the record-setting field the fastest in Indy history was thinking much about speed on Thursday.

“You know, we’ve been consistent all month,” said Kanaan, a regular in the rival CART series but a rookie at Indy. “I wasn’t looking for the fast lap at all. I got a good draft and I was able to go quick, but I was more concerned about how my car is running in traffic.

“I made a couple changes. We only had 20 laps, but it worked fine.”

Mark Dismore at 218.674 mph was the only driver slower than 220 mph in the two-hour session.

“Right now, we’re just trying to come up with a good race car, and it’s hard to do on Carb Day when you’ve got only a little track time,” he said.

“By the time you do your systems check, you scuff tires and everything, you end up with anywhere from 20 to 30 laps,” he added.

Greg Ray was third at 224.975 mph, followed by Gil de Ferran at 224.949 mph, Robbie Buhl at 224.839 mph, Michael Andretti at 224.532 mph and Jimmy Vasser at 224.439 mph.

Helio Castroneves, the defending race winner, was ninth at 224.191 mph, just ahead of Bruno Junqueira, whose 224.140 mph was considerably slower than the four-lap average of 232.342 mph that put him on the pole for Sunday’s race.

“We just went out and made a few full-tank runs, and the car was really good,” Junqueira said. “We made a few small adjustments and I’m getting excited for the race on Sunday.

“It is an advantage starting from the pole because there won’t be any traffic in front of me,” added Junqueira, who finished fifth here last year as a rookie. “Hopefully, there won’t be any traffic in front of me the whole race.”

The 33 cars completed a total of 771 laps without incident. Two yellow flags interrupted the session, one for rookie Rick Treadway’s stalled car on pit road and the other for debris.

Other than trying to get the race day set-up just right, Carburetion Day is also the last chance to make sure everything on the cars, which have been virtually rebuilt since last being run, is working properly.

“We’re quite happy with the balance of the car and all that good stuff, but we had a gearbox problem. We could have dropped out of the race with that,” said Arie Luyendyk, a two-time Indy winner.

Luyendyk was 31st Thursday at 220.756 mph.