Everyone seems to reccomend the red line, but you can also take the green line, which will be much less crowded. You can get off at 35th, same as the red line, but two blocks to the east. Just take a right out of the station, and the ball park is right there accross the expressway. I usually take the green when headed to the cell after work, just because that train is closer to my office, and the red line can get absolutely jam packed on game nights.