The back yard was to be a stadium, with vinyl posters along the fence. The dugout was the designated place for the gifts to be opened.
This is a close up of one of the banners,from Vista Print.
The cake table had a framed photo of the sign at Wrigley Field. Yes, this is a real sign! My son was at the stadium and took the picture for me, about a year before the party, and sent us an 8" x 10" copy. They really did sign a Jonathan Bowen! The party was the perfect time to use it.