There are two main improvements that are driving the Cardinals second half success that they didn’t have in the first half. The first is a vastly improved bullpen, which is benefiting from a combination of addition by subtraction, better pitchers taking the more important spots, and some good old fashioned luck. The second is defense.
I wanted to see just how much better the team has been on defense in the second half as compared to the first. Now obviously, this isn’t a situation where I need to prove my conclusion. Nobody in their right mind would argue the first half defense was better.