If you decide to drive and park in downtown, I say you park at the Marriott valet. It's FREE if you spend $25 at Latitude. Uh, a steal! Because you would pay $10-$15 for parking anyway and get nothing out of it. 

We came for the baseball game and it was happy hour at Latitude. $5 for wells, $5 for domestic drafts, and $5 shots! Totally worth it. 5 people, 5 drinks =$25 well spent! Covered for parking, and went to a good cause that we would have spent $0 on one beer at Petco park! Saved us a bunch pre-drinking here. We also got to go up to their "sister" bar, Altitude. 

There weren't any food happy hour deals, which I was bummed after a hard day of work and no food--straight to alcohol it is. And their wells isn't like the cheap alcohol. Vodka well was like Skyy, and not like Pavlov or something nasty. The place wasn't busy.

Next time you're going to park for a ball game and want to predrink, take it to the Marriott valet and spend $25 here (easily, that's 5 drinks!)