An example of a different format...

Game: Yankees double-header vs. Rays on 9/7/2009

Steiner Sports has 2 bases from this game currently for sale on their website. Here are the URLs to both items:

http://auction.mlb.com/cgi-bin/ncomm...unbr=110992452
http://auction.mlb.com/cgi-bin/ncomm...unbr=110991532

Item #1 is listed as a Rays-Yankees Game Used Ball (Game 1)
Item #2 is listed as a Rays-Yankees Game Used Ball (Game 2)

This may lean towards the theory that any item from a double-header can be from either/or game of that doubleheader.