I think this is why the Brewers will struggle in the playoffs. The batters think anything on the edge is a ball and wait for the walks. That works until you face great pitching.
Good job by Stallings in that inning. Fully expect Brewers to send him down after the game to maintain "roster flexibility" instead of fielding the best team.
I think that system was dumb. When to call for a challenge should be when you think it's wrong. If you keep using up challenges because you have a bad eye, then you get a red light. They have unlimited challenges if correct.