Say what you will, but over the course of a season, a great starting pitcher is exponentially more valuable than a great closer. But on Sunday, Jake McGee was the most valuable player in the Rays-Tigers game. He entered the game in the 7th inning after Hellickson had allowed 2 hits and a walk to load the bases and proceeded to retire all three batters he faced to keep the Rays’ lead at 3-1. How do we know that McGee’s heroics outweighed Hellickson overall outing and Jose Lobaton‘s 3 for 3 with 2 RBI? A nifty metric called Win Probability Added.
McGee entered the game with the leverage index at 4.79, 479% higher than league average. Before McGee came in, the Rays’ probability of winning had dipped from 84.7% at the start of the inning to just 55.7%. And then McGee slammed the door and at the end of the inning, the Rays had a 90.6% chance of winning. For his efforts, McGee had a WPA of .352, meaning that he alone with his 3 outs won over a third of the game for the Rays. Lobaton had a great game, but his WPA was only .236. And after his 7th inning collapse, Hellickson’s WPA dropped to just -.129–WPA doesn’t care that the runs didn’t score, only that Hellickson put the Rays in a dire position. And watching the game, how could you possibly dispute any of those numbers? Jake McGee only threw one inning. But in doing so, he played a bigger role than anyone in winning the Rays the game.