"Ground Chuck" Getting Pounded

In April and May, Charlie "Ground Chuck" Morton used a sinker-centric approach to induce weak chopper after weak chopper. Opponents hit a collective .252, got on base at a .329 clip and slugged just .315 against Morton.

Since the calendar flipped to June, however, hitters have put Ground Chuck through the meat grinder. Morton has turned every hitter into Dustin Pedroia out there, allowing a .335/.410/.473 triple-slash over the past two months.

There doesn't seem to be much difference in the location of Morton's sinker:

 Morton's sinker location, April-May 2011

Morton's sinker location, June-July 2011

But hitters are making louder contact:

In-play opponent slugging percentage vs. Morton's sinker, April-May 2011

In-play opponent slugging percentage vs. Morton's sinker, June-July 2011

To be sure, some of the drastic change in Morton's performance is due to poor luck -- he had a .286 batting average in April and May, but his BABIP since is .382. But it's also true that batters are doing more extra-base damage.

Opponents had a paltry .063 Isolated Power (slugging minus batting average) over the first two months, and a .138 ISO in June and July. That June-July ISO is right around the league average, which is a problem considering that Morton doesn't strike out many hitters and has so-so control. He needs to limit doubles, triples and homers to make up for his other shortcomings.

Perhaps with ample video and advance scouting reports on Morton's new delivery and pitching approach now available, batters have simply become more accustomed to the fact that he throws sinkers so often. Seven or eight times out of ten, a batter is going to guess right if he thinks he's going to get a low-90s pitch that tails to Morton's arm side.

Morton's best hope at turning his season around and doing something to avoid being a bunching bag to left-handed hitters (they have a .380/.458/.542 triple-slash in 2011) might be a little more variety. In particular, he has shown a promising high-70s curveball with plenty of break. Curveballs tend to have less of a platoon split than other pitches (sinkers have the largest split), and if thrown more often, the breaking ball would keep hitters from waiting for a sinker in that one spot.

Check out the pitch break and velocity of Morton's curve (blue), compared to his sinker (orange):

 Release velocity and pitch break of Morton's curveball and sinker

Hitters aren't just passive zombies at the plate -- they make adjustments based on the information at hand. The word has gotten out on Morton's sinker. Now, it's time for him to make an adjustment of his own by being less predictable on the mound.

Transforming Morton

The following video made the rounds in the baseball blogosphere on Friday.  It compares the way Charlie Morton of the Pittsburgh Pirates and Roy Halladay of the Philadelphia Phillies throw the two-seam fastball.

Morton worked on copying Halladay's delivery during the off-season.  His pitching stats certainly have improved.

The two seam fastball is supposed to sink.  In 2010, it didn't sink all the time:

Charlie Morton, fastball movement, 2010.In 2011, Morton puts more of the density below the X-axis:

Charlie Morton, fastball movement, 2011.That more closely matches what Roy Halladay throws:

Roy Halladay, fastball movement, 2010-2011.There is one big difference that remains between the two, however.  Roy works both sides of the plate with his fastball, Morton works middle-in to righties, middle-out to lefites.  He doesn't throw to the catcher's right hand:

Charlie Morton, fastball pitch frequency, 2011.Morton gets the same movement as Halladay, but can throw it to multiple locations yet.  That may be the lesson for next winter.