(This is the last of a four-part series by noted motorsports reporter Will Buxton chronicling the incredible 2016 journey of Alexander Rossi, from little-known Verizon IndyCar Series rookie to champion of the historic 100th Running of the Indianapolis 500 presented by PennGrade Motor Oil. If you missed them, catch up on Part 1, Part 2 and Part 3 here.)

After refueling problems earlier in the 100th Running of the Indianapolis 500 presented by PennGrade Motor Oil forced Alexander Rossi into an alternate fuel-saving strategy, the Verizon IndyCar Series rookie circled the 2.5-mile Indianapolis Motor Speedway oval as conservatively as possible – trying to achieve what he thought was an impossible fuel-mileage target to complete the final 36 laps without a pit stop. Or worse, running out of fuel on track.

On hit pit stand, Rossi’s braintrust led by team co-owner/race strategist Bryan Herta calculated that he would run out with a lap to go, but they pushed on and the No. 98 NAPA Auto Parts/Curb Honda slowly climbed higher up the scoring pylon as the other front-runners were forced to peel off for a late splash-and-go.

With three laps to go, Andretti Autosport teammate Carlos Munoz pitted from P1. Alexander Rossi was leading the Indianapolis 500. On fumes.

“I was expecting to run out on (Lap) 197 or 198. That was my own math,” Rossi said. “I didn’t know what the team had calculated.

“When Carlos pitted, Bryan came on the radio and told me I was P1, but it didn’t register. I was having to be so thoughtful and mindful of the fuel and not screwing up, that I just didn’t hear him. The thing you have to realize is that, at Indy, it is harder to drive slow than to drive fast because at low speed you don’t have the downforce. The car becomes completely unstable and you start fighting it. My mental capacity was one corner at a time, making sure I didn’t do anything stupid, making sure I didn’t throw it all away, while still keeping that fuel number.”

Somehow, Rossi saw the white flag signaling a final lap. Just 2.5 of the longest miles he’d ever endure remained. Through Turn 1 the team saw his fuel pressure starting to drop from data received on the pit stand. Out of Turn 2, the driver felt the engine cutting out. “Full throttle!” was the passionate call from Herta on the radio. Rossi took the car to 205 mph. At Turn 4, the engine died, dry of Sunoco E85R ethanol.

“That’s when the nerves hit,” Rossi exhales. “Sitting there (coasting to the finish), waiting for someone to fly past.”

But they didn’t. The checkers flew for Rossi first. He’d done it.

“You want to know what the very, very first thing was in my head?” he asked. “Honestly, I was just so pumped I’d made a fuel number which I didn’t think was possible. My ego went through the roof. I was like, I am the (best) at saving fuel!

“But then the most amazing thing happened. Because the engine was off, I had this incredible and unique experience. As I got to Turn 1, I realized I could hear everyone (cheering in the stands). I heard the whole place erupt. How many race winners, let alone Indy 500 winners, get to experience that? And it just hit me, all of it. It was overwhelming.”

From there, it was and remains a blur.

“If you watch the post-race (ceremonies), you’ll see I have no clue what is going on,” he admits. “You pull in and there’s like 100 people and you’re trying to figure out which one is the person telling you where to go. I had no clue. I didn’t even know how to put (the victory) wreath on. I didn’t know what to do with the milk. I knew absolutely nothing. In the end my PR rep ended up standing behind the cameras with a scratch pad writing instructions for me with a Sharpie. I don’t remember much of it, to be honest.

“All I really remember is seeing my dad (Pieter). I saw the emotion in him and it all came home. The journey we’d been on. And the ultimate validation that this was so right. This was where we were meant to be.”

For Alexander Rossi, the decision to leave behind everything to which he had dedicated his racing life in Europe was a massive and potentially disastrous call. And yet, on the biggest stage possible, it had proven itself to be the best move he’d ever made.

“It changed the direction of my career, no question,” Rossi says. “Even before the month of May, I was starting to really enjoy INDYCAR and what it was all about, just going to racetracks and driving as hard as I could. How welcomed I’d been into the series and into Andretti and how, despite my lack of knowledge and, frankly, appreciation of everything due to the fact I’d just never even been to an INDYCAR race before, Andretti just literally from drivers, engineers, executives and everyone got me up to speed and helped me. That was an amazing experience.

“The fact we won the 500 gave me an opportunity to stay here, to stay with Andretti and Honda and to strengthen all these amazing relationships we’ve made.”

Now, 25-year-old American returns as the reigning Indianapolis 500 champion for Sunday’s 101st running. His face now cast in sterling silver and adorning the Borg-Warner Trophy, how will this year differ to his first experience?

“In some ways, I want it to be different and in some ways, I don’t.

“I’m looking forward to the lead-up. I know what the race means now and I know why we do all the media. I understand the place that the race holds for the city of Indianapolis, for INDYCAR and for American motorsports. But at the same time, I think the fact that I always treated it like any other race ended up being an advantage and is something I will try to do again.”

But what of that secret? The way to make that incredible fuel number of 3.9 miles per gallon into a 4.7? Will he now share it?

“No I won’t!” he laughs. “The only frustrating thing is that my engineer (Tom German) already moved teams (to Rahal Letterman Lanigan Racing), so the secret is probably out. Plus, Ganassi (with its four cars) now have Honda engines so they probably know, too. But having lived it, I can tell you, it’s one thing to have the theory, but it’s quite another being able to put it into practice.”

Alexander Rossi never expected to be racing Indy cars. Now he returns to “The Greatest Spectacle in Racing” as the Indianapolis 500 champion. Its 100th, his name etched into racing history forever. At the beginning of a new life which brought this Californian home.

To race. To win. To stay.