Yankees History: Fun with WPA

The Win Probability Added statistic within the context of a single game can be interesting to observe. For those unaware, FanGraphs defines WPA as “the change in Win Expectancy from one plate appearance to the next and credits or debits the player based on how much their action increased their team’s odds of winning.”

WPA is also fun to look at because one at-bat can change so much about it. For example, if a player goes 0-for-4 but then comes up with two outs and a runner on in the ninth with his team down a run and hits a two-run homer, then they’re almost certainly going to have the best WPA of the game. That remains true even if all their other at-bats are double plays or whatever. The point is that you can do a lot of damage in not a lot of time. In fact, it can do you a lot even if you appear in just one plate appearance all game.

Let’s take a look at the good and bad of how much WPA a Yankee player could rack up in the shortest amount of time possible.

I know, I know, but we have to start with a bad one for reasons that will become clear in a minute.

On June 21, 1988, the Yankees went into the bottom of the ninth with a 6-1 lead over the Tigers. Neil Allen started the inning, but allowed a single and a walk and was pulled in favor of closer Dave Righetti. He got two outs, but also allowed a single and then walked two batters home, making it 6-3. Manager Billy Martin then brought in Cecilio Guante to face Alan Trammell. That would be the only batter Guante faced, but it wasn’t because he retired him. Guante allowed a walk-off grand slam to the future Hall of Famer as the Yankees completed a meltdown:

Before the at-bat, the Yankees had a 91-percent chance at winning and Guante’s WPA was -0.908. That’s the worst of any pitcher in team history in a game where they only had one batter faced.

Notably, that would also be the penultimate game of Martin’s managerial career. The Yankees lost another game to Detroit the next day, and George Steinbrenner fired him for would be the final time after that loss.

As for Guante, he is also third all-time on the “lowest Yankee WPA in one batter faced” games for another appearance just over two weeks before the June 21st one, although that one’s not as much on him. He came in and induced a groundball with two outs and a two-run lead in the ninth of a June 4th game against the Orioles. However, a throwing error by Mike Pagliarulo allowed all three runners that were on base to score and give the Orioles a win. What a brutal run.

On the positive side of things, Danny McDevitt increased the Yankees’ chances of winning by 46 percent when he came in with runners on the corners and got a game-ending double play in his only action of the day in a 1961 game against the Red Sox.

As far as hitting goes, the best ever swing came courtesy of Jason Giambi on June 5, 2008. The Yankees were down to their last strike and trailed by a run when Giambi stepped to the plate as a pinch-hitter. With Hideki Matsui on first, Giambi homered off B.J. Ryan:

It was an 89-percent swing in win expectancy.

On July 30, 1961, the Yankees were actually favored to win according to Win Expectancy despite losing with one out in the ninth inning. That’s because the bases were loaded when Héctor López stepped to the plate as a pinch-hitter. The Yankees basically only needed one semi-decent hit in two potential bites of the apple to win the game. That did not happen. López grounded into a game-ending double play, a swing of 53 percent in WPA.

Baseball is a team sport where you usually need multiple good players and performances to win a game. Yet, so much can hinge on just one little plate appearance within a game.