Alexander Rossi has signed a new "multi-year" deal with Andretti Autosport, after months of speculation that he could move to another IndyCar team such as Penske.
The announcement also coincided with team boss Michael Andretti confirming that his outfit will continue with Honda engines and Rossi is seen as a key driver for the manufacturer.
Rossi, who won the 2016 Indianapolis 500 in his first IndyCar season, currently lies second in the '19 championship and is locked in a title fight with Penske's Josef Newgarden and Simon Pagenaud.
"It feels good to continue with Andretti Autosport," Rossi said. "Over the past four years we've built a very strong team with great chemistry, and I believe that we have the tools necessary to win races and championships.
"I'm looking forward to not just calling this my team but my home in the IndyCar Series. "Michael [Andretti], J-F [Thormann, Andretti president], Doug [Bresnahan, chief marketing officer] and the entire team have been working very hard to put all the pieces of this deal together, and it's definitely a relief to have the future settled and be able to focus on the championship fight ahead of us."
Rossi had been linked to a possible move to Chevrolet-powered Penske, despite his strong Honda connections, and he has competed for the squad in the IMSA SportsCar Championship this season.
Sam Schmidt - co-owner of Arrow Schmidt Peterson Motorsports - had also previously told Autosport he was interested in the 27-year-old, but that he expected him to remain at Andretti.
Andretti started the 2.2-litre V6 twin-turbo engine era in 2012 with a drivers' title for Ryan Hunter-Reay using Chevrolet power.
It then switched to Honda but has yet to win the drivers' title since Hunter-Reay's success.
Ted Klaus, the president of Honda Performance Development, said Rossi's Andretti deal was "an important moment".
He continued: "Andretti Autosport is unquestionably one of the premier teams in the NTT IndyCar Series, and we are gratified to earn their confidence for the foreseeable future.
"At HPD, our first goal every season is winning the Indianapolis 500, and Andretti Autosport has won more 500s for Honda than any other team.
"That said, HPD is fortunate to work with multiple high-calibre racing organisations.
"This commitment from Andretti Autosport strengthens our entire effort as we move into the next era of Indy car competition."
NAPA Auto Parts appears set to remain as the primary sponsor for - one of the keys to Rossi and Andretti remaining partners - with AutoNation also staying put.
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