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The 2010 season has been a great one for rookie performances in both leagues, but it's easy to get caught up in the excitement of a young player's production and overvalue them going forward. Every fantasy owners knows there is nothing quite like the feeling you get from being right about a player before anyone else in your league can be, and sometimes, that feeling lingers just a little too long. Over the next few days, we will take a look at some of the top rookie performances from the AL and NL and try to gauge their value going forward to give you a sense of what you should expect, and whether they should be someone on your radar for 2011 or even someone you should be keeping.

Austin Jackson leads all American League rookie hitters in VORP thanks to a line of .298/.353/.409 with 24 steals (in 29 attempts, an 83 percent success rate). The batting average is useful, and though he doesn’t add much in the way of power he has played all year long (627 plate appearances is another reason he sits atop the rookie leader boards) and has those steals to lean on.

It's tempting to want to hold on to him because of his youth, early major league success and, if you had him in an auction league, what is probably a low, low price tag. There are reasons to be leery though, most notably, his BABIP, which sits at .405. Now, Jackson is the kind of hitter, thanks to the combination of speed and his ability to either hit the ball on a line or keep it on the ground, who can put up a higher BABIP on a consistent basis. He had a .384 BABIP at Triple-A last year in the New York Yankees' system, and was at .346 the year before that. That .346 BABIP is the lowest he has posted as a professional over a full season, which should give you some idea that this is a repeatable skill of his. The question is just how high should we expect it to be at the major league level in 2011, because believing it must be over .400 again is just setting up for eventual disappointment. That is, of course, unless Jackson has the power to control the path of the ball with his mind, but that's a skill reserved for a different Jackson entirely.

His line has given him a .282 TAv, which is 12 points above the average in center field. Let's assume his BABIP dips to .360 in 2011, which could drop his overall line to something more like .265/.325/.380 or so, roughly speaking. That's not great, but it's not far from the average in center field either (the current average line for center fielders is .262/.330/.410) and Jackson has the steals to punch up his value on a fantasy basis—it's also close to what PECOTA forecasted for him in 2010 to begin with (.262/.322/.400). That's assuming no legitimate improvement from Jackson, who will be just 24 years old in 2011—if he can cut his strikeout rate down by a few percentage points, he could recoup some batting average and bump up his on-base and slugging numbers as well. That's no small concern either, as Jackson whiffs like a power hitter—the problem is that Jackson is sans power.

He always struck out in the minor leagues as well—25 percent of his plate appearances in 2006, 19 percent in 2007 and in 2008, and 22 percent in 2009. This year he's at 25 percent, but if he could lower it more towards his 2007-2009 levels (an average of 20 percent) it would do a lot towards improving as a hitter. It would make his line look very similar to his 2010 production in fact, but as it would be more legitimate, you could depend upon him to repeat it.

That being said, it's no guarantee he does improve, though his progress since the last time he struck out this much as a pro is an encouraging thought. The worst case scenario is the one outlined above, where Jackson is an average center fielder who steals bases for you, but there's a chance he can repeat his 2010 season, without the massive BABIP assist, assuming he can bring those whiffs down. If you have him at a low price (full disclosure: I have Jackson on a team I'm rebuilding at the cost of $1) then there's enough upside to want to hold onto him assuming you have the keeper slots to do so. In a straight keeper draft with no price tag though, Jackson may be someone you can wait on in the draft-the upside is good, but it's not that good that you can't wait to pick him up later.