THQ core games boss Danny Bilson has revealed that Saints Row 3D started as an Xbox Live Arcade project before Nintendo pushed for a 3DS adaptation.
Both versions will be seen through to fruition, and having the existing code-base meant an easy conversion when Mario came a-knocking.
"Nintendo really wants to launch with a very balanced portfolio. They really don't want it to feel like a kiddie platform. They were very clear: they really wanted Saints Row on it," Bilson told Industry Gamers.
"Now, we know how those go sometimes: sure, the first party wants it, but is it really going to work? The interesting thing about the game is we were already making it. We were already making it as our Xbox Live game and in 3D also. It's designed for 3D already.
"I believe it will do great," he added, "especially if Nintendo is going to go mature and really do a big mature campaign on it. It's a killer game."
Bilson said both games have been designed "to sell Saints Row 3". He also revealed that both 3D games will unlock content for each other.
"I don't know if I was clear about that, but all of our extension properties all connect and unlock things in each other," he stated.
Saints Row 3 is due to appear sometime before March 2012.