Baltimore Orioles fans have seen plenty of young arms crash and burn over the years. Entering 2012, Jake Arrieta appeared close to joining the likes of Matt Riley, Adam Loewen, Brandon Erbe, Hayden Penn and Chris Tillman in the pitching prospect graveyard. The 6-4 righty, given a $1.1 million bonus out of TCU back in 2007, compiled an 85 ERA+ in 2010-11 while posting the highest walk rate (4.4 per nine innings) of any American League starter tossing at least 200 frames. Arrieta's career prospects were quickly sinking.
A sinker, however, is a big reason why Arrieta is thriving for the shockingly competitive O's. He has cut his walk rate down to 2.1 per nine innings and boasts a 116 ERA+ after shutting down the Yankees and ending Ivan Nova's 15-game winning streak last night. Arrieta threw 44 sinkers against New York, getting strikes with 30 of them (68 percent). The 26-year-old is throwing the pitch more often -- and more accurately-- in 2012.
From 2010-11, about 21 percent of Arrieta's pitches were classified as sinkers. He often missed off the outside corner to lefties (inside to righties):
Arrieta threw just 42 percent of his sinkers in the strike zone, well below the 50 percent average for MLB starting pitchers over that period. But this year, Arrieta has increased his sinker usage (to about one-third of his pitches) and is pounding the zone with the 93 mph offering:
Arrieta has located 52 percent of his sinkers in the zone. Those extra pitches over the plate haven't come at the expense of more extra-base hits, either. Hitters are slugging .308 against Arrieta's sinker in 2012, down from .452 in 2010-11.