Josh Beckett of the Red Sox finished May with an impressive 1.00 ERA. One reason for his excellent numbers came from Josh's performance against left-handed batters. They posted a .197/.282/.211 slash line against the right-hander, good for a .239 wOBA. Notice that he used the whole strike zone against lefties:
Beckett pitched lefties low and inside, a place where left-handed power hitters especially like to drive the ball. Josh, however, owned the inside edge:
That big blue area came from the effective use of his cut fastball. Beckett threw his fastball high and more toward the middle of the plate. That set up the cutter, which he kept inside:
Looking at the break of the fastball and cutter you can really see how it fooled batters.
The big red circle represents the fastball, the little yellow spot down and inside represents the cutter. Batters see the fastball, they get used to it coming in and breaking a little bit toward them. Then Beckett unleashes the cutter at close to the same speed and and direction, but the ball breaks in and down instead of staying up and over the plate. Beckett got batters to chase 38% of the cutters out of the zone, and received called strikes on 28% of those pitches. He lefties in and out of the zone, turning an area of strength into a weakness.