Helio Castroneves has admitted that his win in Sunday's IndyCar season opener in St. Petersburg was important for both himself and his Penske team after enduring the worst season of his career last year.

The three-time Indianapolis 500 winner came into the weekend following the first winless season of his career. His last victory had come at Motegi in 2010, and he said that opening his 2012 campaign with a win would be an important boost.

"For our group, it's important," Castroneves said. "We never lost confidence. We never stopped believing. Especially this off-season, with the tests that we've been doing, we've been up there in testing, helping each other, so we never stopped believing.

"Last year, unfortunately because of many issues – some of them were mine, some of them were bad luck, some of them were because of the new rules we have with the double-file restarts – I have to say I did not felt comfortable at that point. Now, with new car, new engine, it gives you a fresh start."

Castroneves admitted that his duel for the lead with Scott Dixon had been difficult, and that he had worried about his fuel after pulling away int the lead.

"I was still with the cold tires. He was very good to keep right behind me," related the Brazilian. "The rules today, you're not allowed to move and try to block or defend your position, because that is considered blocking. I think everybody understand that now – at least I do. So, nothing I could do. He passed me clean, fair and square.

"Now I took advantage. I think it was traffic in the middle, in the mix, and I was able to get a great run on Dixon. I thought, 'OK, he's not going to make it easy for me.' I remember last year, things didn't go well. He showed me another direction, which is fine. I decided to go to the outside, and I braked as deep as I can where everybody brakes. That was awesome, because the car sticks. I'm like, 'Yes, I made it!'

"As soon as I turned, I kept going. I took advantage of the tires because I knew the red tires were very good in the beginning. They said I'm OK on the fuel. I was just pushing, pushing. I keep going away, going away. I'm like, 'Are you guys sure?' 'Yes, you're fine, you can save a little bit of fuel.' I'm like, 'Wait a minute, I'm OK, not OK?'

"I knew it was 20 laps to go. It's a long, long way. I've got to save a little bit of tires. That's what I did. Yellow never came. There was a little scenario with [Marco] Andretti with two laps to go. I was not understanding what's going on. But after that, I made the move, I was just taking it very, very easy, make sure we have a great result this first race of the season."

Castroneves reckoned the race to have been a good start for the new IndyCar chassis and engine formula as well.

"Maybe in some part of the race, it was not much passing, but in some others it was a lot of passing," he said. "I guess the cars were able to hold well. I thought was very good. I thought was clean. The cars looked great. Speed-wise, Will broke the track record, so sure the car is good.

"I believe it was crucial. We've got new cars, new manufacturers, obviously. We have a new person in charge, some new rules. I mean, there are so many new things. We didn't know a lot until the first race. Everybody learned  a lot today."