's defense has got him in the news and not in a good way. Andrew Baggerly made some critical remarks about his defense and his poor offense this spring, which stirred the pot and got people talking. If Tejada doesn't play well, the team could be in big trouble.

Rory Paap (newly of Bay City Ball) wrote a post talking about the trouble Tejada is having defensively and brought up in passing that the Giants in-house options of and . They are not really major league ready, but the Giants should weigh how much they are worth compared to Tejada.

I thought that was a great idea and took the liberty to create some break-even points for how bad Tejada has to play or how well the kids have to play to replace him. The biggest factor is trying to determine the offensive projection for Tejada because that's where the majority of his value comes from. I ended up using three different projections, as summarized below.

The Bill James Projection (0.348 wOBA, very bullish)*, My 2011 Projection (0.328 wOBA, in the middle) and the Marcel Projection (0.308, most bearish)*. For Crawford and Adrianza, I used the ZIPs projection because it actually had something in there for both of them. In the graphs I used, only Crawford is worth considering because they both project very similarly, with Crawford slightly ahead with a 0.287 wOBA.

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To explain the graph, the starting point is the projected WAR for each projection system assuming 150 games and for Tejada -3 runs defense and for Crawford +7 runs defense. As you move right, the wOBA for Tejada decreases by 1% of what was projected. It's the opposite for Crawford; as you move right, his wOBA increases.

If Tajada is as good as Bill James thinks, then he's nearly 2.5 wins better than the in-house options. If he only plays as well as I expect, that drops to 1.5 wins. If Marcel is right, then it narrows to 0.25 wins better. Crawford can close the gap by outperforming his ZIPs projection. To surpass Tejada's Marcel projection, he must do 2% better; to surpass Tejada's Crazy Crabbers projection, he must do 8% better; and to surpass Tejada's Bill James projection, he must do 15% better.

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If the defense falls completely apart, things look really bad. This graph assumes that he falls to his career worst level of -11 UZR/150 level that he posted with the Astros in 2009. At this level, Crawford already is the better choice if the Marcel projection is the most accurate and in the others, the gap in performance between them is much smaller. With a good year from Crawford, he should take over as the starting shortstop.