After getting out of a jam in the top of the first, Jordan Schafer (the Astros' leadoff hitter) took the first pitch from Zack Greinke and hit a line drive to center field. The Brewers' center fielder ran straight ahead, dove for it, and missed, so the ball got by him. It looked for a minute like Schafer was going to get an inside-the-park home run, but he ended up with a triple.
Three pitches later, Jose Altuve hit a slow roller to first base. Schafer scored, and Greinke covered the bag but the umpire ruled Altuve was safe at first. (from where we were sitting, it looked very close) Greinke then got upset and spiked the ball, and the umpire ejected him! (the manager then ran out of the dugout and got himself ejected shortly thereafter)
So that was dramatic. Then, the Brewers had to find a new pitcher who had to warm up very quickly - usually when you bring a pitcher in, he's been warming up in the bullpen for a while. If a pitcher gets injured, then the replacement pitcher gets extra warmup pitches, but apparently that isn't true when a pitcher gets ejected :-)
So the rest of the game was pretty weird - the Brewers ended up using 7 pitchers, and based on their stats, they were probably the bottom of the barrel ones. Wandy Rodriguez started for the Astros and went 5 good innings, and then the Astros also went through 6 other pitchers, which made the game drag on for a bit. The Astros were up 6-0 at one point, but the game never really seemed out of reach for the Brewers which kept it somewhat interesting. (the final score was 6-2)