Now that the season is over, I can stop looking at minor league players in my examinations and focus on some major leaguers.
First up is speed demon center fielder Rajai Davis, who seemed to break out this year. Is he for real? Let's take a look.
Davis spent 2008 hitting .243/.272/.346 between San Francisco and Oakland. He was 27 at the time, and it looked like he would forever be a below-average hitter whose speed (29-for-35 in steals) made him an acceptable backup outfielder.
Many A's fans spent April and May 2009 calling for Davis' release as he continued to struggle early, but the A's kept him.
Suddenly, in the second half of the year, he caught fire, became the everyday center fielder, and finished the year with a .305/.360/.423 line nobody saw coming. His .354 wOBA was well above average for the CF position, and he went 41-for-53 in steals as well.
If we look deeper, we can find that Davis is not as bad as he was in 2008, but not as good as he was in 2009.
Before we get there, though, let's look at what he did improve. Davis more than doubled his BB/K ratio (.41, up from .20) and cut down on his popups (13.6 percent, down from 18 percent in 2008). Popups are basically automatic outs, going for hits one to two percent of the time on average, so minimizing them is crucial to a hitter's success.
However (and here's where the problem starts), Davis' line-drive rate and groundball rate both declined from 2008 to 2009, which is bad for a speed-oriented player like himself.
That's not to say that his line-drive rate (20.0 percent) and groundball rate (45.6 percent) are poor; they're actually quite good. However, his 2008 levels (22 percent LD, 48.2 percent GB) are more ideal.
So why did Davis hit .242 in 2008 and .305 in 2009? Luck.
It's been shown that taking a player's line drive percentage + .12 is a decent formula for predicting batting average on balls in play. That means that Davis should have a BABIP of about .340 in 2008 and .320 in 2009.
Instead, his 2008 BABIP was .287 and his 2009 BABIP was .366.
What am I getting at here, you ask? Basically, I'm saying that, with average luck, Davis is not as bad as his 2008 numbers suggest nor as good as his 2009 numbers would have you believe. If a .366 BABIP makes him hit .305, and a .287 BABIP makes him hit .242, and his actual deserved BABIP is about .330, that puts Davis' expected batting average in the .270-.285 range.
Sorry for the inundation of math there.
Anyway, Rajai Davis appears to be about a .280 hitter. I'd project a .280/.335/.395 line from him next year, which makes him a passable starting center fielder, but far short of a star.
Defensively, Davis posted a quality 10.6 UZR/150 this year in center field. That strong defense, when combined with his speed and the okay offense, not to mention his low salary, makes Davis a good option in CF for 2010.
Davis is something of a slap hitter, but he has some meat on his frame and isn't completely at a loss for power, with 27 doubles and three homers last season. He is one of the fastest players in baseball.
He shows average plate discipline and isn't afraid to choke up and play for contact with two strikes. Davis is a decent bunter but could improve his skills to get more infield hits. Being a right-handed hitter, he needs to bunt extremely well to get bunt singles.
Defensively, his instincts are below average, and he struggles to get breaks on balls, especially those hit over his head. He has so much speed that he usually outruns these mistakes. Davis plays aggressively shallow to make up for his arm strength, which is average at best. His throws often lack accuracy, especially to the plate.
Overall, Davis' speed is what drives him, and there will come a point in a few years where he can't handle center anymore. At that point, he will lose a ton of value a la Juan Pierre, but until then, he's an exciting player who can start 150 games per year and help a team win in a variety of ways.