Every year, a hot prospect comes into the league that garners buzz and excitement. Last year, Evan Longoria was that player, going as high as the 10th round in many drafts. Despite starting the year in the minors, Longoria eventually made his arrival and paid great dividend to those who took a shot on him and stuck with him through his trip to Durham last April.

For every Longoria, however, there’s plenty of hot prospects like Alex Gordon, Clay Buchholz, and Delmon Young, whose success isn’t immediate. In fact, most prospects take a while to adjust to major league pitching and hitting, and the upside of these players in their rookie years is a long-shot to match the performance of boring veterans. Even Longoria is an example of this. Last April, ESPN’s Matthew Berry asked readers whether they wanted Longoria or “boring, unsexy, no upside, owned-in-only-58-percent-of-ESPN.com-standard-leagues Aubrey Huff.” As well as Longoria did in 2008, by the end of the season, Huff did better.

This year, Baltimore Orioles catching prospect Matt Wieters is the guy who fantasy owners are drooling over.

For the reasons above, I exercise extreme caution about young players, but Wieters may be the exception. Today, ESPN’s top baseball scout, Keith Law, releases his top prospects going into the 2009 season with Wieters at the top of the list, compared favorably to Mark Teixeira. 

Imagine, if you will, Teixeira with catcher eligibility. In fantasy drafts, that might command the top pick overall, even ahead of Hanley Ramirez, Alex Rodriguez, and Albert Pujols. That’s Wieters’ upside. 

Of course, it’s unreasonable to expect such production right away, and fantasy owners shouldn’t lose all senses to draft the guy ahead of those with a greater probability of contributing to success in the 2009 season. Currently, Wieters is going anywhere from the 10th round to the 14th. Since the talent curve at catcher drops significantly after the first four, gambling on Wieters’ upside with a reasonable investment like this can certainly pay off.

What’s more intriguing is what I may expect to be “The Matt Wieters Effect.” Let’s say that Wieters lives up to his hype as Longoria did last year. If Wieters approaches the expectations that many like Keith Law envision for this player, he could be in the first round very easily going into 2010. Maybe even a top-5 pick. The ramifications of such a scenario, if it were to unfold, would likely lead fantasy owners to make Wieters the poster child for prospect payoff. Those who play fantasy baseball might go to sleep, dreaming of the next Matt Wieters, and lust after any top prospect who commands a dose of hype.

Perhaps it’s wise for keeper owners (and maybe even those who play in re-draft leagues) to think ahead of this curve and plan for the day when prospects on the edge of promotion oblige top trade value. Anybody who plays in a keeper league may find it hard to trade for Matt Wieters or David Price today. But how about Carlos Santana, the Indians’ catching prospect who is #13 on Keith Law’s list? Santana may never amount to Wieters’ equal in actual value, but as the next top catching prospect to come to the majors in the post-Wieters era, he could potentially derive some tremendous associative value.