What to Wear??

A very important client invited me to a Yankees game next week after work. I need the perfect outfit and need help figuring out what that is...! My dilemma stems from the fact that a baseball game is obviously a casual event, but I'll be attending after work and with some VIPs (probably all men). There is also a good chance that I'll be schmoozing with some other potential clients. What should I wear????

-Amanda in NY