10/13/2009 at 03:50 PM EDT
He's this year's Indianapolis 500 champion
and the winner
of Dancing With the Stars
' season four, but Helio Castroneves has his sights set on a whole new adventure: fatherhood.
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."