INDIANAPOLIS – They call him “Taku,” and now he will be remembered.

It was easy to overlook Takuma Sato before. He shared his Andretti Autosport garage with five teammates, four of them with higher profiles.

When the green flag dropped on the 101st Indianapolis 500 presented by PennGrade Motor Oil on Sunday, the motorsports world was keeping a close eye on another foreign driver, two-time Formula One world champion Fernando Alonso of Spain.

Defending Indianapolis 500 winner Alexander Rossi, another Sato teammate, had qualified on the outside of the front row. The team’s best driver in recent years has been Ryan Hunter-Reay, who won the 2014 Indianapolis 500 and the 2012 Verizon IndyCar Series championship.

Then there’s team owner Michael Andretti’s 30-year-old son, Marco, who has shared his father’s affinity for “The Greatest Spectacle in Racing” by almost winning five times — finishing second once, third three times and fourth once.

That left rookie Jack Harvey, who was making his series debut, and Sato, who wasn’t retained by AJ Foyt Racing and became an offseason free agent. Sato, from Tokyo, eventually switched places with Carlos Munoz, a two-time Indy 500 runner-up with Andretti who was hired by Foyt this season.

But when the checkered flag ended a dramatic Sunday duel at Indianapolis Motor Speedway, Sato and his No. 26 Andretti Autosport Honda fended off a challenge from three-time Indy 500 winner Helio Castroneves of Team Penske to celebrate his greatest victory in 124 career series starts.

“It’s beautiful,” Sato said. “I dreamed of something like this since I was 12.”

“‘Taku’ did an awesome job,” Michael Andretti said.

Sato became the first Japanese driver to win the Indy 500. Tora Takagi had the highest previous finish of fifth in 2003.

“This will be mega big,” Sato said of the anticipated reaction in Japan. “I cannot imagine how it’s going to be.”

After his only other series victory at Long Beach in 2013, Sato went home for a press conference and was met by about 300 media.

“I know they (flew) over from Japan today,” Sato said of his supporters. “Many, many people came.”

He recently admitted he was still uncomfortable on the high-speed 2.5-mile oval at IMS, and the results reflected what has been a challenging and ongoing adjustment from previously racing in Formula One on just road and street courses. His best Indy 500 finish in seven previous starts was 13th, twice.

But Sato showed he’s still fearless, just like on the last lap of the 2012 Indy 500, when he tried to dart inside for the lead on Dario Franchitti and crashed in Turn 1.

“This time, I was pointing in the right direction, wasn’t I?” Sato said, referring to his attempt to overtake Franchitti, who benefited from the ensuing caution flag to celebrate his third Indy 500 win.

Andretti has won three of the last four Indy 500s to boost his career total to five, which ties Lou Moore and Chip Ganassi (four with his own team and one with a team co-owned with Pat Patrick) for second on the all-time list behind Roger Penske’s 16.

“Maybe when I’m 80 years old, hopefully I’ll have more wins than Roger,” Andretti said of the 80-year-old Penske. “That’s our goal.”

Andretti, 54, continues to atone for what’s missing on his racing resume when he drove, leading the most laps (431) without an Indy 500 victory. The six cars were the most he has ever entered in this race.

Although his cars were strong for much of the afternoon, Andretti couldn’t help but become concerned after Hunter-Reay and Alonso dropped out with plumes of smoke trailing from their engine covers. In a race with a record 15 lap leaders, Hunter-Reay led 28, Alonso 27 and Rossi 23 compared to Sato’s 17.

Sato, aside from everything else, stayed patient. He turned the fastest lap of the race at 226.190 mph on Lap 150.

“There’s many times where he was in a difficult situation, and he would get out of the situation,” Michael Andretti said. “He showed a lot of patience. But then when he had to go, he went.”

Castroneves, bidding to tie Foyt, Rick Mears and Al Unser with a record-tying fourth Indy 500 win, took the lead on Lap 194. But Sato stayed close and pulled off a sling-shot pass just before the yard of bricks start/finish line at the end of Lap 195.

“I knew I could do it,” Sato said. “But just, you know, waiting (for) the moment. The last few laps, they were the moment.”

Sato was a late bloomer who didn’t see his first race until 10 and never raced a car until 20. Sato, 40, becomes the 14th Indy 500 winner 40 or older and first since Eddie Cheever in 1998.

“Michael put everything together, six drivers,” Sato said. “I think we were (a) happy team.”

Overlooked no more, “Taku” ended up being the happiest driver of them all.

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