Several of 2013’s superlative pitching performances came from pitchers who had exceptional control. Koji Uehara was fourth in line to be the Red Sox closer when the year started, but he ended up with the best ERA (1.09) of all qualified relievers. He had just seven unintentional walks in 74.1 innings. Another example is Adam Wainwright. He has always been a great pitcher, but he cut his ERA by a full run from 2012 to 2013 as he reduced his walks per nine from 2.4 to 1.3. Bartolo Colon had a 2.65 ERA, the sixth-best of qualified starters. That was despite his 5.5 strikeouts per nine, sixth-lowest of the group. Colon issued just 29 walks in 190.1 innings.
Colon may be the most fascinating case. In his prime, Colon was an elite pitcher with tremendous stuff. Now, he is in his 40s and averages less than 90 mph on his fastball. However, rather than shy away from his diminished fastball, Colon has relied on the pitch more and more. In 2013, he threw it 86 percent of the time. Despite the frequency and slowness of the pitch, Colon enjoyed the best ERA of his career.
Colon is an extreme case of a pitcher who relies entirely on control—he threw more than 50 percent of his pitches in the strike zone in 2013—and it works for him. How important is control overall and how well does it correlate with performance? To investigate, we divided the 81 starters who qualified for the ERA title in 2013 into quartiles based on the percentage of pitches they threw in the strike zone. We labeled the 21 pitchers who threw the most strikes as Grade A Control Pitchers, the 20 pitchers who threw the next most strikes as Grade B Control Pitchers, the next group is called Grade C, and the final 20 pitchers are Grade D. Here is how they performed