For a pitcher, above everything you need a good fastball. You don’t have to throw it 95 MPH, but it between its velocity, movement, and the way you command it, it has to be something that can be used with confidence against major league hitters. But unless a pitcher has the greatest fastball in the world, his fastball can only be the start of his arsenal. Every pitcher needs other pitches that can fool hitters if they’re geared up for the fastball and in turn make the fastball better by giving hitters more effective pitches they have to keep track of. There will always be games where one pitch works great and another doesn’t at all, but on the whole pitchers have to mix in all their pitches to find consistent success in the major leagues. However, against left-handed batters this season and his entire career, David Price has gone staunchly against that.
Each pitcher is going to throw their fastball at a different frequency depending on how good it is and how good their other pitches. That is quite a simple idea–but it is far from the only factor. Many pitchers will also switch up their fastball usage quite significantly based on the count. They’ll get ahead using mostly fastballs before going to their secondary pitches to put hitters away. Another consideration is whether they’re facing a same-side batter or one batting from the opposite side. Pitchers will throw their fastballs at different percentages of the time against righty and lefty batters, using it less to whichever side to which their secondary pitches work best. Using data from Brooks Baseball, we find that the 90 qualifying starting pitchers in baseball this season tended to use their fastball 5% more to opposite-side batters with two strikes. Each pitcher used his fastball at a different rate depending on its effectiveness, but on the whole, they tended to throw it less to same-side batters with two strikes. A possible explanation is that most pitchers trust their breaking ball against same-side hitters more than their changeup against opposite-side hitters and make up for the difference by using their fastball more. There were notable exceptions–several pitchers, mostly ones with overbearing fastballs like Clayton Kershaw, Max Scherzer, Justin Verlander, and Price, used their fastballs 15% more against same-side hitters. Why would that be? For those four pitchers, their fastballs are great enough to retire hitters by themselves quite often, and adding in the deception they have from the platoon advantages makes it so they can stick with their fastball most of the time. Why show your breaking pitches if your fastball is just that good? But there’s a fine line between keeping your secondary pitches in reserve and overusing your fastball, and David Price may have gone too far.
Against right-handed hitters in 2013, Price has used his fastball just 38% of the time with two strikes. He has relied heavily on the cutter he discovered a few years back, throwing it 33% of the time, and he has also throw his curveball at 17% of the time and his changeup at a 12% clip. Against lefty batters with two strikes, though, it has been a different story. His fastball usage jumps to an insane 80%, with his curveball coming in at 13%, his cutter at 4% and his changeup at 2%. There are several pitchers who throw their fastball at an 80% clip, and some pitchers reach that mark against hitters from one side but not the other, but not a single one of the qualifying starting pitchers in baseball aside from Price has a difference of 42% or more between his two-strike fastball usage between same-side and opposite-side batters. In fact, no other pitcher has as high as a 30% difference. Why does Price go almost all fastballs versus lefties while going with the soft stuff against righties? As we saw above, Price has more secondary pitches he trusts against righties. His cutter has emerged as a weapon and his changeup is an effective pitch as well. Against lefties, Price is down to his only real split-neutral secondary pitch, his curveball, and it’s closer to average than plus. Luckily, Price’s fastball is dominant enough, especially against left-handed hitters, that he does just fine. But there are times that it really costs him, with the 2-run triple Price allowed in the 5th inning of his start against the Mariners immediately coming to mind.
David Price is a true ace, but his lack of that knockout secondary pitch against lefties holds him back just enough to make him a great pitcher but not one of the four or five best in baseball. Price doesn’t have that overbearing changeup that befuddles righties and lefties alike like Jeremy Hellickson and Alex Cobb. So while on the whole, Price can beat hitters with the velocity, movement, and command he has on his fastball, the reason his failures do happen is quite often because of the lack of that dominant secondary pitch behind that fastball.