10/13/2009 AT 3:50 PM ET
Castroneves, 34, and girlfriend Adriana Henao are expecting their first child – a girl – in January, the racer announced.
While the couple originally considered naming their daughter Indy – later deciding it was a “little too much” – they have since settled on Mikaella.
As for tying the knot with Henao, Castroneves says no plans have been made, but considers marriage the “natural next step.”
“This year started very difficult,” Castroneves said, referring to the tax evasion charges he was acquitted of in April. “The middle was kind of a ‘Wow!’ and now this. This is a great ending for the book.”