Matt Klaassen of Fangraphs explains [when the Cardinals should think about walking Papi](http://www.fangraphs.com/blogs/when-to-walk-david-ortiz/):
> In the bottom of the first, the Cardinals need to have fallen behind by a pretty wide margin in order to justify walking Ortiz. For example, they need to be down by five runs with two outs and a runner on second for the walk to Ortiz (who would be coming up bat for the second time in the inning!) to make sense. In the bottom of the second, much the same is true — the Cardinals would need to be down three or four runs (it is close) with one out and runners on second and third or two outs and a runner on second to walk Ortiz. As the game progresses, the number of situations in which intentionally walking Ortiz with a right-handed pitcher slated to face him and the following batters increases, but just slightly, and it is close. They mostly occur with one or two outs and runners on second and third, or two outs with runners on second or third.
> The Cardinals would need to be behind (and again, I’m simplifying to avoid just listing every case): by at least three in the third, two in the fourth, or one in the fifth. By the bottom of the sixth, walking Ortiz with a righty on the mound is recommended even in a tie game with runners on second and third and one out or a runner on second and two outs. In the seventh, with second and third occupied and one out, the Cardinals might even want to walk Ortiz if they are up by one.
As you can see, the answer is not as clear as “just walk him every time he comes to the plate”.[^fn1]
[^fn1]: Which, unsuprisingly, is what some people are suggesting