After just 5⅔ innings in the major leagues, right-handed pitching prospect Jarrod Parker is on the Diamondbacks' postseason roster.

Kirk Gibson: Okay, Parker. You're up. Game One is yours. Sit down, Kennedy.

Ian Kennedy: Wait, what?

Gibson: This Maddon cat is onto something. If a 22-year-old with nine innings of experience can shut down the Rangers, imagine what a 22-year-old with five innings of experience can do!

Jarrod Parker: Okay. Let me throw up for an hour or so, and I think I'll be okay.

Well, Parker isn't actually going to start a game, but it's still a bit of a surprise that he's on the roster at all. Nick Piecoro of the Arizona Republic does a good job explaining why:

It’s not that I don’t think Parker is a better option – he probably is, based off the way he pitched in the second half of the minor league season, in the Double-A playoffs, in his big league debut Tuesday – it’s just that he’s in his first year back from Tommy John surgery, has already surpassed his targeted innings (by a long shot) and has never pitched in relief before.