I’ve got a little spreadsheet that tracks Win Probability Added (WPA) during a game, and I thought I would put it to good use this year by following specific games and writing them up with a running WPA commentary. This is my first foray into this new territory (other than some games at the end of the season last year), and I hope you let me know if you find it worthwhile or worthless.
The Reds pitted past Met phenom Paul Wilson against new Met old mon Pedro Martinez yesterday, and each team had a 50% chance of winning at the beginning of the game. Which gives us with a WPA conundrum right off the bat.
Home teams win about 55% of all games, as Tom Meagher described a few weeks ago. So the question with WPA is whether we should give the home team a 55% chance of winning (and give the road team 45%), or stick with the more theoretically correct 50%. For now, I’m sticking with 50%, but it’s a debate that will almost certainly come up again.
Kaz Matsui, of the Matsuis of New York, hit a solo home run into the rightfield stands with one out in the first, quickly increasing the Mets’ WPA to .584. In the bottom of the first, however, Griffey and Casey both singled, which lowered the Mets’ WPA back down to .517, and Adam Dunn followed with a smash into the centerfield seats, flipping the WPA in the Reds’ direction to .716, which is a credit for Dunn (and a debit for Martinez) of .276. Rapid swings of direction from single swings of the bat; a harbinger of swings to come.
The Mets threatened in the top of the second, with runners on first and second and none out (lowering the Reds’ WPA to .604), but David Wright hit into a double play and the Mets failed to score. However, the Reds didn’t threaten against Pedro Martinez again. Pedro settled down after the Dunn homer, and recorded eleven of the next twelve outs via the strikeout.
The Mets broke back in the top of the third and tied the game on a Carlos Beltran home run after a Jose Reyes single. Reyes’ single was important, but Beltran’s HR was the big blow; it lowered the Reds’ WPA from .719 to .524 for a Beltran credit of .195. If nothing else, WPA does help you understand the power of the home run. Remember Weaver’s Third Law: “The easiest way around the bases is with one swing of the bat.”
The score remained tied at 3 through the sixth inning, and the Reds’ WPA hovered between .500 and .600 during that time. Martinez was hot and Wilson was not too bad either, though he did give up a couple of doubles. The Mets threatened to score again in the sixth, with runners on first and second and none out, reaching a WPA of .636. But Wright once again hit into a double play and the Mets once again did not score. In those two at bats, Wright was debited a WPA of -.263, which means his two double plays hurt the Mets almost as much as Dunn’s home run.
The Mets finally broke through in the top of the seventh, after David Weathers relieved Wilson for the Reds. Reyes led off with a double and Matsui followed with a beautiful sacrifice bunt that he almost beat out for a hit. The sacrifice was an interesting call at this stage of the game.
The bunt actually lowered the Mets’ WPA from .613 to .603, but it increased the Mets’ chances of scoring exactly one run from 35% to 48%. When you include the fact that Matsui almost bunted for a hit, this wasn’t a bad strategy, especially considering what happened later in the inning. However, the Mets would later rue the fact that they gave up an out that may not have been necessary.
Beltran followed up with a single through the drawn-in infield (if Reyes hadn’t been on third, the infield would not have been drawn in), increasing the Mets’ WPA to .708 and crediting Beltran .106 points. At this point, Beltran was looking like a $17 million man. Unfortunately, he was next caught in a run-down while attempting to steal second, which was a WPA debit of -0.44. Given what happened next, this out would definitely haunt the Mets.
Mike Piazza followed up with a double (just missing a home run) and Floyd homered off Kent Mercker, who had just entered the game. The Floyd homer was huge (.199 credit) and increased the Mets’ WPA to .891. Things looked good for the Mets; three-run leads are hard to overcome in three innings.
The Reds did manage to score a run thanks to a Jason LaRue double in the bottom of the seventh, but that barely made a dent on the Mets’ WPA, which was .875 after the seventh. The entire eighth inning and the top of the ninth passed without incident, and the Reds had only a .083 WPA entering the bottom of the ninth. What’s more, Met relief ace Braden Looper was taking the mound.
Looper didn’t register a single out. Austin Kearns singled through the hole in left for a big hit (WPA of .176) and Dunn blasted another home run. The homer was huge, of course — worth .458 WPA (nearly half a win) and it raised the Reds’ WPA to .634. Which Joe Randa rounded up to 1.00 by blasting another home run. Game over thanks to a ninth inning worth .917 WPA! And three outs still to go.
This was a Three True Outcomes game. Specifically, nineteen strikeouts and six home runs were the currency of the game. Fielding didn’t play much of a role, either positively or negatively. It all came down to the sluggers, which is reflected in the WPA leaders board:
Player WPA Dunn 0.684 Randa 0.368 Beltran 0.264 Floyd 0.261 Minty 0.123 Reyes 0.122 LaRue 0.086 Koo 0.082 Wagner 0.027 Graves 0.014 Matsui 0.014 Griffey 0.007 Aybar -0.001 Anderson -0.008 Jimenez -0.009 Kearns -0.020 Piazza -0.030 Aurilia -0.031 Wilson -0.041 Cruz -0.050 Valent -0.070 Casey -0.132 Martinez -0.133 Mercker -0.199 Weathers -0.204 Wright -0.217 Looper -0.908
Finally, here is a graph of the Reds’ WPA throughout the game:
References & Resources
My WPA spreadsheet incorporates the work of a number of great baseball writers and analysts, including Tangotiger, Keith Woolner, Doug Drinen, Phil Birnbaum and Jon Daly. Many thanks to all of them.