During an expansive sit-down 10 days ago with a small group of reporters at IndyCar's season-finale at Laguna Seca that spanned how he managed to hold onto Alex Palou to the future of sports TV, there were but a few topics Chip Ganassi wasn’t willing to dive into.

One of them? The future of Chip Ganassi Racing's 18-year-old development driver Kyffin Simpson, the son of David Simpson, whose green Ridgeline Lubricants livery has been a frequent sponsor on the grid since May 2022 and whose multi-year deal with Ganassi is said to be worth tens of millions of dollars -- leading some in the paddock to wonder (incorrectly, according to the team) if the elder Simpson had taken a minority stake in CGR.

"We just throw darts. We don't really play much," Ganassi joked when asked what the future might look like for the Cayman Islands-native. "I don't know what it is yet. I would like to share it with somebody, but I don't know what the hell it is."

He does now.

In a shocking development to the free agent market, CGR will run a fifth full-time car in 2024 for Simpson, who will easily become the youngest driver on the grid with his 19th birthday a couple weeks away. He'll join a decorated lineup that includes six-time champion Scott Dixon, two-time (and defending) champion Alex Palou, 2022 Indy NXT champ Linus Lundqvist and reigning Rookie of the Year Marcus Armstrong -- the latter two also making their full-season debuts in 2024.

CGR's 2024 lineup will mark IndyCar's first five full-time driver roster since 2020, when Andretti Autosport ran Zach Veach, Alexander Rossi and Ryan Hunter-Reay alongside Colton Herta -- in a team alliance with Harding Steinbrenner Racing -- and Marco Andretti -- co-entered with Bryan Herta Autosport.

"It's been incredible working with Chip Ganassi Racing as their development driver over the last couple years, and I've been able to learn so much. I am very excited to be making the next step to IndyCar with this team," Simpson said in a team release. "I'm really looking forward to working more closely with the entire team and the drivers, and I also want to thank Chip and (managing director Mike Hull) for giving me this opportunity."

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Simpson took the 2021 Formula Regional Americas title, winning seven of the 18 rounds, in a success that helped springboard him to the first of two campaigns in Indy NXT in 2022-23. As a rookie a year ago, Simpson finished 9th in points while running for TJ Speed Motorsports to start the season -- before a shift to HMD Motorsports to finish out the year -- in a campaign that included two 5th-place finishes in a field that included at least 11 (and often 13 or more) cars.

In 2023, he dropped a spot to 10th while continuing to run with HMD, but managed to bag two podiums (3rd on the IMS road course and 2nd at Mid-Ohio) while missing the round at World Wide Technology Raceway and being disqualified in the Barber race early in the season. Presently, Simpson races in the European Le Mans Series, where he and his Algarve Pro Racing teammates sit 1st in the LMP2 standings halfway through the six-race schedule -- bolstered by a win in the 4 Hours of Le Castellet.

Simpson also registered a class win in LMP2 (3rd overall) with Tower Motorsports in IMSA's 12 Hours of Sebring this year, along with both a class and overall win in the Asian Le Mans Series at the 4 Hours of Dubai.

According to the release, Simpson's signing completes CGR's driver lineup for 2024, seemingly taking the team out of consideration for a veteran looking to try and land an Indy 500-only deal with the team that has consistently been the fastest in the field in recent years.

"We welcome Kyffin as a teammate to our IndyCar program. He has been integrated into a Chip Ganassi Racing multi-year defined development program, which now provides the opportunity at open-wheel's highest level," Hull said in a team release.

Given Honda Performance Development's firm ceiling of running 15 full-time IndyCar entries in recent years, Simpson's promotion to full-time status and CGR's five-car lineup would seem to only further complicate Andretti Autosport's decision on whether to drop down to three full-time entries, or to stick at four despite losing their fourth Leaders Circle entry by just a single point after the controversial end to Devlin DeFrancesco's season-finale that left the team one point short of $1 million or more in guaranteed prize money next season.

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When reached for comment, an HPD official told IndyStar that a decision on whether to stick with 15 full-time engine leases -- 5 for CGR, 3 each for Andretti and Rahal Letterman Lanigan Racing and 2 each for Meyer Shank Racing and Dale Coyne Racing -- for 2024, or to add another in the midst of IndyCar's move to hybrid engines, should Andretti find the funding and the right driver fit to push HPD to add one more, has yet to be decided.

This article originally appeared on Indianapolis Star: IndyCar: Chip Ganassi promotes Kyffin Simpson to 5th full-time car for 2024