(Charles Krupa/AP)

For the past two years Mark Teixeira has been one of the most frustrating players on the Yankees. In 2009, after signing for eight years and $180 million, Teixeira proved his worth, hitting .292/.383/.565 (.402 wOBA) and powering the league’s best offense. But since then his production has dropped to more human levels. In 2010, amid nagging injuries, he slumped to .256/.365/.481 (.367 wOBA). This year he’s at .248/.346/.512 (.370 wOBA). No one has welcomed this recent development.

That isn’t to say that Teixeira has played poorly. In fact, he has been one of the most productive Yankees in the last two years. In that time he has created 50.6 runs above average, which falls behind only Robinson Cano and Curtis Granderson. He also has a 130 wRC+, which also falls behind only those two. In terms of his place in the league, he has created the 17th most runs in the last two years, and has the 22nd highest wRC+. To say he’s been bad is a gross misstatement. He has been, despite his slumps, a top 20 player.

The disappointment stems not only from his hefty contract, but also from his drop-off after 2008 and 2009. In those two seasons he was second in the league with 89 runs above average and seventh with a 149 wRC+. He has gone from being a superstar to being a very good hitter. It’s probably the toughest downgrade in sports. There’s something special about a superstar. We think of them as different from their peers, that extra two percent better. Very good players help teams win ballgames and championships, but it’s hard to appreciate a very good player when he was so recently a superstar. (And is getting paid like a superstar.)

This season Teixeira has produced his numbers mostly through power. His 34 homers ranks third in the majors and his .263 ISO ranks fifth (third in the AL). But that’s really the only way he’s helped out. His .248 batting average is a career low, owing mostly to a .231 BABIP that ranks fourth lowest in the league. His walk rate has taken a slight hit, too, dropping to 2009 levels despite the 40-points-lower batting average. Again, that has translated into a productive season, as demonstrated above. But it’s not a superstar season.

One aspect adding to the frustration over Teixeira is that he’s been all or nothing this year. Again, he’s smacked 34 homers, and he’s done that in 32 games. In those games his, unsurprisingly, killing the ball, hitting .369/.440/1.230 in 141 PA. That amounts to about a quarter of his total PA and games played. The problem comes in the other three quarters of his games and PA. In those, 93 and 414, he has hit .207/.314/.263. When he’s not hitting a homer, Teixeira isn’t doing much of anything else.

That there’s a large gap in Teixeira’s numbers when homering and when not homering comes as little surprise. When he hits a home run he’s obviously being more productive, so therefore he’ll produce much better numbers when he’s performing the single most valuable act in baseball. The issue with Teixeira is the expanse of the divide.

Take Curtis Granderson as a counterexample. He has homered 35 times in 33 different games, and has hit .403/.473/1.256 in those games. In the games he did not homer, however, he remains decently productive: .231/.340/.335. Those aren’t great numbers by any stretch, but with the OBP, in addition to the 17 doubles and 9 triples, makes Curtis a somewhat productive player when he’s not hitting a homer. That’s just not the case for Teixeira.

The most frustrating aspect of the Tex divide is that there’s not much the Yankees can do about it. They could drop him in the order if they wanted, but that would only diminish the value they get from the 25 percent of games in which he does hit a homer. Dropping him in the order also only makes room for a player who creates fewer runs than Teixeira. Sure, there are plenty of benefits to having Gardner atop the lineup, but it’s not as though the Yankees are holding back a speedy guy with a .380 OBP.

If the biggest issue with Teixeira this season is frustration, that’s probably a good thing. Frustration is merely an emotion, something we feel when we see something that falls below our expectations. Teixeira has surely done that. For the second straight year he’s dipped below the superstar level of production he established from 2008 to 2009. Despite that, he’s still put together two generally productive seasons, and has been one of the Yankees’ two or three best hitters in that span. It is something of a problem that he’s essentially useless in 75 percent of his games. But you never know when one of the 25 percent is coming. And when it does, it’s a big boost to the Yankees lineup.

(AP Photo/Kathy Willens)

Two weeks ago, Mark Teixeira returned to the Bronx to kick off a ten-game homestand with a .240/.344/.493 season batting line, above-average on-base and power numbers, but hardly what we’ve come to expect from the $180M first baseman. He was stuck in an ugly short-term rut (.200/.222/.257 in the first eight games after the All-Star break) and a disappointing long-term slump (.232/.327/.460 in his previous 343 PA). The terms “slump” is relative here, because that’s basically a league average OBP with a stellar .228 ISO. Either way, Tex was looking pretty bad at the plate.

Then he returned home, and then things started to go his way. Teixeira homered and drew two walks in the first game of the homestand, and over the full ten games he went 13-for-39 (.333) with four homers, five walks, and just six strikeouts. A pair of hits on Monday opened the road trip, and last night Tex picked up three more hits, including a homerun from each side of the plate. His season batting line is up to .256/.352/.527, which is much more pleasing to the eye than that .240-something monstrosity from two weeks ago.

If you take a look at the spray charts since the start of the homestand, you’ll see that Teixeira really isn’t doing anything differently. He’s still extremely pull happy (here’s the spray chart vs. RHP, vs. LHP), so it’s not like he’s shortened up in an effort to dunk the ball into the opposite field or anything. Or maybe he has and it just hasn’t yielded any results yet, who knows. Tex’s season BABIP sat at .226 coming into the homestand but has since risen to .236, and you can see the gradual improvement here…

I remember seeing at least two balls eke their way through the shift on the homestand, and that’s part of the regression monster. Tex has definitely changed his approach since coming to the Yankees, making a conscious attempt to hit more fly balls, presumably in an effort to take advantage of the short porch. There’s nothing wrong with trying to hit for more power, but more fly balls means a lower BABIP, and that means a lower batting average. A lower batting average means a lower OBP, and OBP is king. In fact, if Tex had a league average walk rate this year (8.2%) instead of his current 11.4%, his season OBP would be .320. I don’t want to think about what it would be without those eight hit-by-pitches.

Anyway, we don’t have to worry about that. Drawing walks is most certainly a skill and getting hit by pitches is also skill (to a lesser extent), so it’s not like Teixeira is lucking into his OBP. Hit Tracker says just one of his 31 homers this year was “lucky,” this shot in the third game of the season, and I don’t think we’d have any disagreement about the enormity of his power. He was struggling in the worst way two weeks ago, and it can be particularly ugly when Teixeira struggles. He’ll pop the ball up on the infield or swing over top of offspeed pitches, which is as frustrating as it gets. He’s not doing that at the moment and appears to be on the his way towards another one of his hot streaks, when he’ll look like the best player on the planet.

It really does seem to be Mark Teixeira week here at RAB. On Monday Mike looked at Teixeira’s disappointing overall numbers, and yesterday I looked at some plate discipline and shift issues. Today we’re going to look at pictures rather than numbers. Many of us suspect that, beyond facing a defensive shift, Teixeira’s woes are at least partially mechanical. We see him up there wagging his bat, and it’s hard not to think that it takes away from his swing. We’re not hitting coaches, of course, so you can take our analysis on that matter with a grain of salt. Yet sometimes video does reveal some obvious issues.

Here’s a shot of Teixeira with the Angels in 2008, in the midst of an incredible offensive run. His stance is pretty basic, slightly opened with his hands up by his ears. I’m not going to dive too far into the technical aspects, since I’m not a trained scout. But there’s nothing that stands out here. Then again, that’s because we don’t yet has a basis for comparison.

Here’s Teixeira in 2009, another year in which he hit phenomenally. The camera angle is different than the one in Texas, so it’s not a perfect comparison. But it still seems close enough. His front leg does appear a bit more open, even though the camera angle is more centered (the Rangers camera is offset in left field). Still, it appears that he’s balanced up there.

This angle is essentially the same as the 2009 one, just zoomed in a bit. I tried to capture it at the same point in the pitcher’s motion, so we’re not seeing him at different parts of his swing. Look at that back leg. That’s way out there, far more open than it was in 2009. His balance does look a bit off, as you might imagine as he changes his center of gravity. I’m not sure how great an effect this has, since he takes his stride towards the center of the batter’s box. But it looks like his stride takes longer with the more open stance.

Another thing you might notice is in the swing itself. I’ll embed the videos here so you can have a look.

2009:

2011:

Maybe I’m only seeing this because I’m looking for something, but in 2009 it appears that his bat just glides through the zone. It’s a quick, easy swing. In 2011 it looks more like he’s clubbing the ball. If anyone else looks at the videos and sees something else, by all means chime in.

Again, as a non-hitting coach and non-scout, I can’t drawn any firm conclusions from the pictures and video presented here. They look convincing enough, as Teixeira’s stands does seem far more open, and his swing doesn’t appear as smooth. Unfortunately, even if this does identify the problem, it doesn’t necessarily lead to a fix. If me, a schlub with a computer and an internet connection, can see this in video clips, I’m certain that the Yankees are aware. But hitters can’t just change like that. Teixeira widened his stance for a reason, likely as a matter of comfort at the plate. It’s a shame if it’s hurting his swing, but there’s not much anyone can do unless he’s willing to make a conscious change. After all, there’s nothing worse than standing in the box while uncomfortable.