If you read the World Series preview, you would have seen Edwin Jackson and Derek Holland predicted to play games three and seven. Obviously, we now know (and really have for a while, I've been admittedly slow at this) that is incorrect, as Kyle Lohse will be squaring off against Matt Harrison tonight, and again in a necessary game seven, with Holland and Jackson occurring only tomorrow.
On paper, this is a win for the Rangers in both ways. You could have a lively debate about Holland vs. Harrison, but the latter was better over the course of the season in ERA, tRA, and FIP: in short, he was better at run prevention and his peripherals backed that up. Holland's FIP looked better if you regressed his rate of homeruns allowed (xFIP), however, which means he could potentially be the better starter in St. Louis, and was better down the stretch run of the season than Harrison. Either way, it is likely a small loss at most, and a large sample of statistics call it a small gain right now.
The larger gain is from the Cardinals going to Lohse twice, rather than Jackson. Jackson's peripherals declined some with a switch to the National League, but overall, he was better peripherally than Lohse, with a slightly higher ERA, despite pitching most of his season in a more difficult league (with designated hitters). Lohse took a step forward this year to become merely a solid pitcher who would not likely make the Texas rotation, while Jackson remained a good pitcher for the third straight season.
Tony LaRussa is not just going to the lesser pitcher (again, on paper) either. He is walking in to a potential match-up nightmare, as well. Lohse throws the changeup more than four times as often as Jackson, and the Rangers just happen to be the second best team in baseball at hitting changeups. Lohse even gives up a few more fly balls, a dangerous tendency against a powerful team like Texas.
Unless the Cardinals know something not listed here, two of Lohse, instead of two of Jackson, is something Rangers fans should be extremely excited about. In the probability model used in the preview, Lohse vs. Harrison came out as the most one-sided game in Texas. That remains true, only moved up a day, and at the same time makes game seven look like a game that comfortably favors the Rangers should it get that far; even on the road.
As far as how the actual switch affects the series probabilities, it would have take the Rangers from 68% to win up to 71% to win before the games were played. Having now played two games, the Rangers come out as 73% to win the series.
There is one other thing that was ignored in the original preview, however: Josh Hamilton's health. He was assumed to be okay, and clearly he is not. With a sports hernia holding him back, the Rangers' lineup is in a bad situation. How much it holds him back we do not really know. If you call him, say, an average hitter, the Rangers dron down to 71% to win the series going forward; thankfully, not a huge drop, but he might not even be average. If you want to say Hamilton is currently as worthless as the average pitcher is at the plate, the Rangers drop down to a 59% chance to win the series. While still favored, it is a serious drop. Right now, the question is how hurt Hamilton is, and that won't be answered until the series is over. Hopefully, it does not end up being the difference between a title and another off-season of regret.
By the way, if you move Hamilton down to, say, seventh in the lineup makes almost no difference in the projection. Seeing him in the heart of the order like this is frustrating, but batting order makes such a tiny difference it is unlikely to matter over the next five games.