There was one weird offseason when no one was quite sure if Formula One legend Ayrton Senna was going to stick with F1. On December 20, 1992, Senna came to Arizona to test a Penske PC21-Chevy. It was the only time Senna ever floated the idea of running IndyCar, and at the time, it seemed like a plausible move.

At that point, Senna was a three-time F1 world champion racing for McLaren, who he won those three championships with. But McLaren’s 1992 car was unreliable, down on power compared to other teams and lacked the trick active suspension that other teams were already developing.

Twenty-five years later to the date, racing journalist Marshall Pruett and filmmaker Travis Long dug deep into the story of Senna’s lone IndyCar test, speaking with those who were there and many who remember its effects on the motorsport world.

A common contact at cigarette sponsor Marlboro had reached out to Roger Penske to see if Senna could have a run in a Penske IndyCar. It was a no-brainer for everyone on the IndyCar side. Senna just showing up to a test instantly boosted the buzz around IndyCar and Penske’s team—much like did for IndyCar when he did the Indianapolis 500 this year.

Senna proved to be the real deal after all—instantly quick, and carrying in more entry speed than anyone expected him to do in the heavier IndyCars. He got a kick out of the more analog IndyCars.

But Senna still wanted to do this IndyCar test to light a fire under McLaren to get a better engine, and sign him to a better deal. It sort of worked: Senna got paid handsomely per race by McLaren, but McLaren’s car still was down on power and Senna ultimately moved to Williams anyway in 1994.

[H/T Alex!]