In limited action in 2008, Nelson Cruz finally started hitting Major League pitching to the tune of .330/.421/.609. Given the small sample size, people openly questioned whether he had actually turned the corner.

Through Friday, April 17, 2009, Cruz was off to a .282/.356/.718 start, more or less a continuation of his 2008 success. Using PITCHf/x data through the first 10 games of 2009 and some stats from Nelson Cruz's FanGraphs profile, here's a little plate discipline analysis to see if it supports his impressive start.

The black boxes in these charts are approximations of the actual strike zone. Based on average PITCHf/x data for Cruz's at-bats, the bottom of Cruz's strike zone is about 1.6 feet from the ground, and the top of his strike zone is about 3.4 feet from the ground. The left and right edges of the zone are approximated at 1 foot to either side of the plate based on half the plate's width (8.5 inches) plus some wiggle room for pitches that scrape the black (3.5 inches). (NOTE: All location graphs are from the catcher's perspective.)

The first chart shows us what Cruz has been swinging at by location and by pitch type.

Based on this chart, Cruz has mostly been swinging at strikes. According to his O-Swing% at FanGraphs, only 20.2% of these pitches are outside of the strike zone. That is the lowest of his career. Since his 2006 Rangers debut, his O-Swing% has dropped every season - 29.4% in 2006, 26.5% in 2007, and 23.1% in 2008.

Notice that Cruz hasn't swung at many pitches near the bottom or near the outside edge of the zone. This has helped Cruz lay off of breaking pitches away. Through 10 games, Cruz had not swung at a single pitch off the outside edge of the plate.

The second chart shows us what Cruz hasn't been swinging at by location and by pitch type.

This chart fills in the obvious holes from his swings chart. There are a lot of pitches in the zone low and away that Cruz has not swung at. According to his Z-Swing%, Cruz has swung at 78.5% of pitches in the zone. Based on that stat, the chart doesn't exactly match up. It appears that he's been taking pitches in the zone more often than 21.5% of the time. This could be the result of the PITCHf/x strike zone not matching up with the zone being called by the umpires.

Without getting in too terribly deep, here's a quick look at the righty-lefty split broken down by location and pitch result. The small sample against lefties in the first 10 games doesn't give us much to look at, but the righties scatter plot is interesting.

The PITCHf/x strike zones for Cruz appears to be pretty accurate. Keep in mind that some of the strikes outside of the zone were swung at.

Let's look at Cruz's Z-Swing% again. My rough count based on my unofficial strike zone suggests a 61:23 ratio or a 72.6% Z-Swing%, which would still be a career high for him. From 2006 through 2008, Cruz's Z-Swing was very steadily between 70% and 71%.

This year, he's swinging at strikes more often, but he's also swinging at fewer pitches overall - 46.8% in 2009 versus 50.8% in 2006, 49.6% in 2007, and 47.1% in 2008.

April 19, 2009 Update: Cruz has reached base safely in all 12 games this season on 13 hits and 7 walks against only 10 strike outs. He is now hitting .289/.377/.667.

The numbers and charts say he's being more selective than ever. This can only be good news for Cruz, the Texas Rangers, and their fans. I believe that Nelson Cruz has finally arrived.

Some other observations:

• Very few pitches have been thrown low and in to Cruz. I wonder if his AAA scouting report says to stay away from that quadrant.
• Righties stand a good chance of getting Cruz to put the ball in play by throwing him up and in.
• Cruz's first-pitch strike percentages by year: 62.3% in 2006, 63.4% in 2007, 52.6% in 2008, 51.0% in 2009. It's a small sample size and might not mean anything anyway, but it is interesting.
• One step further, Cruz is seeing fewer strikes than ever: 52.5% in 2006, 52.4% in 2007, 50.2% in 2008, and 45.7% in 2009. Combined with the stat above, I'm pretty sure this means something.
• One concern: what happens when opposing pitchers start hammering that outside corner?

News broke late this winter that Texas Rangers RHP Brandon McCarthy would be experimenting with a slurve, a pitch half-way between a slider and a curveball. It was later confirmed that this pitch was intended to replace McCarthy's curveball. I had always believed his curveball was a plus, so this news left me confused.

Yesterday afternoon, Brandon McCarthy debuted his new slurve against Cleveland and PITCHf/x was ready to go. On television, the new pitch didn't look that new, seemingly just a little harder with a little bit sharper break, and more than one person wondered if McCarthy was throwing both a slider and a curve ball.

I grabbed the PITCHf/x data from yesterday's game (April 9, 2009), and decided to compare it with a similar outing. I settled on McCarthy's April 9, 2007 start at home against Tampa Bay. In each start, PITCHf/x identified 4 different pitch types: fastball, curveball, slider, and change up. PITCHf/x data is never perfect, but there's still a lot of great information.

Let's first compare his release points from the catcher's perspective.

Brandon McCarthy's April 9, 2007 pitch release points.Brandon McCarthy's April 9, 2009 pitch release points.

At first glance, it appears that McCarthy's release point has moved about 6 to 10 inches toward third base in the past two years. While definitely interesting, this may or may not actually be the case. In 2007, release points were measured at 55 feet from the back corner of home plate, but the 2009 release points were measured at 50 feet from the back corner of home plate.

Taking a bit of a deeper look reveals that McCarthy's release of his change up is very consistent with that of his fastball with a few stragglers straying up a couple of inches. In 2007, McCarthy's curveball release was a little higher and a little closer to first base, but in 2009, his curveball/slider release is noticeably higher but directly above his fastball release.

Take a look at the pitch movement scatter plots below. Vertical movement is calculated compared to gravity - an approximation of the Magnus effect. This means that zero vertical movement is equal to gravity's effect, while a negative number drops more than gravity and a positive number drops less than gravity.

Brandon McCarthy's April 9, 2007 pitch movement.Brandon McCarthy's April 9, 2009 pitch movement.

Based on the PITCHf/x data shown in the graph, McCarthy's slurve is measurably different from his 2007 curveball. To further illustrate the difference, I grabbed velocity data for the two pitches as well. His average curveball velocity in the 2007 game was 73.47 mph, and his average slurve velocity in the 2009 game was 79.81 mph.

The most important difference between the old curveball and the new slurve is pretty simple: control. In the 2007 game, McCarthy threw 40% (10/25) of his curveballs for strikes. In the 2009 game, McCarthy threw 75% (15/20) of his slurves for strikes.

Yesterday, McCarthy threw 10 of 13 change ups for strikes. He had outstanding overall command of his off-speed stuff, but he really struggled with his fastball command, throwing only 34 of 60 (56.7%) for strikes.

I've noted this in the past, and it's still a major issue. McCarthy has a tendency to drag his arm behind his body when he throws his fastball. This is usually caused when the front shoulder "flies open" by turning toward home plate before the arm is ready to throw. The pitching arm tries to play catch up, but pitches usually wind up high and a tick or two slower when this happens.

In the 3rd inning, pitching coach Mike Maddux trotted out to chat with McCarthy. When he left, McCarthy's fastball jumped from 86-90 to 89-92 for his last 2.1 innings, and he was throwing it down in the zone. PITCHf/x is missing 5 pitches in this span, but after the visit, McCarthy rattled off 10 strikes on his next 12 fastballs.

Outside of that stretch, McCarthy threw only 50% strikes with his fastball. On the up side, Maddux appears to be on top of this, and I expect improvement in this aspect of McCarthy's game throughout the season.

Here are some quick shots:

• In the 2007 game, McCarthy's fastball was 10" to 15" above gravity, and his curveball was 8" to 13" inches below gravity. That's a visual 18" to 28" of vertical separation between the two pitches. I don't have a comparison ready, but that's a huge difference.
• McCarthy's fastball is straighter than ever. He's getting better back-spin, so the ball might appear to rise more, but his fastballs are all clustered around zero horizontal movement. In the 2007 game, he was getting a lot more arm-side movement.
• McCarthy is a tall guy, but it's pretty crazy that he lets go of the baseball when it's nearly 7 1/2 feet off the ground. A fastball to the bottom of the strike zone travels vertically down nearly 6 feet!
• Joey Matschulat at Baseball Time in Arlington took a look at McCarthy's PITCHf/x data as well - Profiling Brandon McCarthy: A Pitch F/X Snapshot.