The speed just hadn't been there lately for Indy race driver Dan Wheldon, before Sunday's Izod IndyCar World Championships in Las Vegas. In Thursday's practice session and in Friday's practice and qualifying sessions, Wheldon noted that his car was some three miles per hour off the pace. 

It is incredibly frustrating, both for me and them, Wheldon said Saturday in a first person piece for USA Today.

But Wheldon said he was ready to be part of an amazing show on Sunday.

Starting in the 34th position among 34 cars in the race on Sunday, Wheldon worked his way up the pack before a massive, fiery 15-car wreck Sunday ended it all.

Wheldon, 33, and a two-time winner of the Indianapolis 500 -- including a win this year -- died from injuries suffered in the wreck after his car flew another in Lap 13 of the race amid the 15-car crash.

The rest of the race was cancelled and drivers did a five-lap salute in Wheldon's honor as Amazing Grace played on loudspeakers.

Many drivers said it was the worst wreck they had ever seen in the sport.

IndyCar is very sad to announce that Dan Wheldon has passed away from unsurvivable injuries, IndyCar CEO Randy Bernard said in a statement. Our thoughts and prayers are with his family today. IndyCar, its drivers and owners, have decided to end the race. In honor of Dan Wheldon, the drivers have decided to do a five-lap salute to in his honor.

Wheldon had been transported to University Medical Center in Las Vegas after the crash, according to CBS News. He was apparently pronounced dead at the hospital. Three others drivers, including championship contender Will Power, were injured. Pippa Mann and J.R. Hildebrand wre also taken to the hospital, complaining of dizziness, but none of the others injured sustained life-threatening injuries.

The 15-car wreck in Lap 13 left Townsend Bell upside down, and smoking cars were cast all over the track, leaving debris almost halfway up the straightaway of the race track oval.

It was like a movie scene which they try to make as gnarly as possible, said Danica Patrick, making her final IndyCar start, according to The Associated Press. It was debris everywhere across the whole track, you could smell the smoke, you could see the billowing smoke on the back straight from the car. There was a chunk of fire that we were driving around. You could see cars scattered. 

Patrick said she had never seen such a mess in my entire career on the track.

Drivers, according to USA Today, had been concerned about the high speeds on LVMS' 1.5-mile oval after they reached nearly 225 mph during practice.

I'll tell you, I've never seen anything like it, Ryan Briscoe said, according to USA Today. The debris we all had to drive through the lap later, it looked like a war scene from 'Terminator' or something. I mean, there were just pieces of metal and car on fire in the middle of the track with no car attached to it and just debris everywhere. So it was scary, and your first thoughts are hoping that no one is hurt because there's just stuff everywhere. Crazy. 

Born in England, Wheldon lived in St. Petersburg, Florida, with his wife, Susie, and two sons.

Wheldon had written in a driver blog in USA Today before the race that he and his team had struggled recently with speed. He said the team had been working hard to fix the problem, and he hoped to be ready for the Las Vegas race.

As long as I can find some speed and keep up with the pack, Weldon wrote in USA Today, I'll do everything I can to put on a show.