Penske Entertainment, the Roger Penske-owned entity that holds Indianapolis Motor Speedway and IndyCar among its assets, said Thursday it has sold one-third interest in the company to Fox.

The sale was described as a strategic investment and partnership designed to launch new growth for IndyCar and it includes a multi-year contract extension for Fox Sports’ media rights deal with the open-wheel series. Fox Sports is in its first season broadcasting IndyCar.

Penske Entertainment expects the sale of part of the company to spearhead innovative and industry-leading racing and entertainment events, heightened digital strategy and immersive content focus, as well as enhanced promotion and star-building opportunities for IndyCar drivers.

“This partnership is built on long-standing trust and a shared vision for the future,” Roger Penske said in a statement. “Fox sees the incredible potential across our sport and wants to play an active role in building our growth trajectory.

“Lachlan Murdoch and his team, starting with Eric Shanks, are committed to our success and will bring incredible energy and innovation to IndyCar.”

Shanks is an Indiana native who grew up attending the Indianapolis 500 and has an affinity for IndyCar racing. He desperately wanted to add IndyCar to Fox Sports’ properties and snagged the TV deal away from NBC Sports ahead of this season.

All races are broadcast on Fox making IndyCar the only series in the United States that does not air any of its events on cable. This year’s Indianapolis 500 on Fox averaged 7.01 million viewers — a 41% increase over last year and a 17-year high.

This season, IndyCar is averaging a 31% increase in viewership year-over-year.

“We’re thrilled to join the IndyCar ownership group at such a pivotal time for the sport,” said Shanks, CEO & Executive Producer, Fox Sports. “IndyCar represents everything we value in live sports — passionate fans, iconic venues, elite competition and year-round storytelling potential.”