LOUISVILLE, Ky. — There are 12 players on the United States Ryder Cup team, and they don't all use the same ball. So in the alternate-shot matches, how do teams decide which ball to use?

I asked Phil Mickelson — the only player on the U.S. team who uses a Callaway ball — if he would encourage his potential foursome teammates to hit a few shots in practice rounds using his Tour ix ball, or if he might practice using another ball.

His answer was perplexing at first, but the more I thought about it, the more sense it made.

"What we do in alternate shot is, I tee off with their ball and they tee off with my ball because we can switch balls each hole," he said. "So it really doesn't become much of a factor, because off the tee it's not going to make too much of a difference. It's the distance control and how it comes off the irons and the trajectory and so forth. And we will be hitting our own balls with our iron approach shots. I just don't think it will be a factor."

Here's a list of the golf balls used by each member of the U.S. Ryder Cup team:

Callaway Tour ix -          Phil Mickelson
Nike One Black -           Chad Campbell, Stewart Cink
Nike One Platinium -    Anthony Kim, Justin Leonard
Srixon Z-URS -              Jim Furyk
Titleist Pro V1 -            Steve Stricker, Boo Weekley, Hunter Mahan
Titleist Pro V1x -          Kenny Perry, J.B. Holmes, Ben Curtis

(Photo by Scott Halleran/Getty Images)