It seemed that Mark Teixeira's two-run blast in the seventh would eclipse Grandy's triple in terms of Win Probability Added, but alas, it did not. While Tex's homer upped the Yankees' chances of winning 28%, Grandy's huge sixth-inning hit was worth 30%.
Here's how it went down -
Francisco Liriano was pitching a great game until the sixth. A five-pitch leadoff strikeout by Nick Swisher seemed meaningless at the time, but was the beginning of the end for Liriano. He used his whole arsenal in the AB and K'ed Swish on a slider. Seeing the fastball, slider and changeup seemed to help the following Yankee batters.
Tex doubled on a changeup two pitches later and Liriano uncorked a changeup for a wild pitch to A-Rod in the next AB before walking him. He didn't throw another changeup all inning. Remember that.
Robbie Cano stepped to the plate, saw two fastballs and singled through the right-side on the second one. Then up-stepped Marcus Thames, who missed a fastball, fouled a fastball and missed a slider (just Liriano's second of the inning). Liriano interspersed a couple fastballs with three sliders to Jorge Posada in the next AB, and Posada lined the third for a single.
At that point, Liriano had thrown 23 pitches in the inning (and 102 for the game) and was tiring. He'd given up hits on a changeup, fastball and slider and had basically shelved the changeup.
We should also remember that the Curtis Granderson who was about to step to the plate was not the same guy who couldn't hit lefties before mid-August (.518 OPS). After working with Kevin Long, he OPS'ed .875 against southpaws after August 11th. Perhaps the Twins didn't notice.
Anyway, Liriano got ahead of Grandy with a slider on the outside corner. Then came a fastball way off the plate. The key pitch was really the third, a good slider off the outside corner that Grandy just managed to check his swing on. (Grandy K'ed on a slider in his last AB; that's called 'experience'.) He was ahead 2-1, and because Grandy hadn't swung at the previous slider, Liriano didn't think he could get him to chase another. He'd been retired on an inside fastball in his first AB (albeit a sharp grounder), and Liriano chose that path again. He didn't execute, instead tossing it out and up, and since the previous three pitches had all been outside, Grandy was looking outside fastball and put his nice, new two-handed swing on it and hit a moonshot to right-centerfield.
Also of note: Perhaps the thought of Brett Gardner and his ML-leading 4.6 pitches/PA - who had already drawn a walk - coerced Liriano into 'giving in' to Granderson with a fastball.
The Yankees went from trailing by a run to leading by a run. It was a great at-bat by Curtis.