Santino Ferrucci will contest the full 2019 IndyCar Series season as team-mate to Sebastien Bourdais at Dale Coyne Racing.
The 20-year-old former Formula 2 racer made four starts with Coyne this season, and was unlucky not to score a top 10 finish at Portland.
His 2019 deal was announced by the Wasserman Media Group, which has signed Ferrucci to a driver representation agreement.
Wasserman's executive vice-president Brad Lusky said: "I like what I see in Santino, both as a young driving talent and as a marketable brand.
"The Wasserman team has a lot of experience in motorsport and I'm excited to see what Santino can do as a young gun in the IndyCar Series next season."
Wasserman's manager of motorsports Mickey Ryan added: "Santino is a hard-working driver and he returns to America with boundless experience in a racecar and with a real technical engineering mindset, which will only help accelerate his learning curve in an IndyCar.
"In my opinion, Santino is exactly the kind of talent and personality that the IndyCar Series needs right now and I'm excited to watch him grow into the next great American champion."
Ferrucci exited F2 mid-season after being banned for a post-race incident with his Trident team-mate and fellow Haas Formula 1 junior Arjun Maini.
Pietro Fittipaldi, one of the other contenders for Coyne's second 2019 seat, recently signed to be test and reserve driver for Haas in F1.
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