I was listening to a podcast a few weeks ago on which Jonah Keri made the statement, "A prospect is a prospect until he's not." Too often people get discouraged by a prospect's poor performance early in their careers but it's important to understand that baseball is an extremely difficult game and players deemed "prospects" are given the label for a reason. They are extremely talented players but players who come up and experience instant success are few and far between. It's important to consider that, if the prospect was tearing up the minor leagues, his stock might actually be higher than it is if his big league production is mediocre. Essentially, prospects aren't busts until they continually fail to provide value and they can be values if other owners sour on them.
Devin Mesoraco, C, Cincinnati Reds
Mesoraco was expected to have taken over the starting catcher job at some point in 2012. On one hand, it may have been foolish for us to think that Dusty Baker would turn the job over to a rookie but, at the same time, Mesoraco didn't exactly force Dusty's hand. After being rated as the International League's top position player prospect in 2011, Mesoraco struggled with the Reds. It's difficult for young catchers to have immediate success at the plate in the big leagues and the task is even more daunting when they don't get consistent plate appearances. In 184 PAs last year, Mesoraco hit .212 with only 5 home runs and 14 RBIs.
His 2012 line left many wondering if Mesoraco would live up to his power-hitting catcher billing. Personally, I still believe in him and don't think we will truly be able to evaluate him until he gets the chance to play more consistently. Having said that, a look at his peripherals will show us that he still plenty of potential. His batting average is what sticks out most to me from 2012 since Mesoraco was supposed to be a rare catcher with the ability to hit for average in addition to power. While a 16.7% LD% is lower than we'd like to see, he's up to 20.4% in 49 PAs this year and he hits plenty of fly balls which should translate into doubles and home runs in The Great American Ballpark. His LD% is a contributor to his .234 BABIP in 2012 and I fully expect that to regress back closer to league average bringing his batting average with it. Mesoraco showed good plate discipline in the minors and he's become more selective each of the past 3 seasons. I'd like to see what Mesoraco could do with more playing time and, until then, he won't lose any luster in my book.
Domonic Brown, OF, Philadelphia Phillies
After seeing Brown hit a home run out of FirstEnergy Stadium and then gun down a runner at the plate the next inning while playing for the Reading Phillies, I refuse to give up on him this easily. As Andrew Ball mentioned in his article this offseason, Brown was considered one of the top prospects in the game in 2011 and was being mentioned in the same group as Mike Trout and Bryce Harper. Even more, he was compared to Barry Bonds and Daryl Strawberry early in his career. Comps can be thrown around loosely at times but those are pretty lofty terms to throw out for any player. Brown was a high risk/high reward pick in the draft and his potential has remained that way since. Matt Kemp is the poster boy for raw talent coming together and the Phillies and fantasy owners are hoping Brown can join him.
Like I said, I still believe in Brown. He finally has the chance to play every day as the Phillies right fielder and he's been playing well enough to keep the job, but he hasn't been lighting the world on fire. Brown will turn 25 this September and was a two sport star in high school. He's still learning some nuances of the game but he is showing signs of putting it all together. His line drive rate has increased from 18.0% to 23.6% since 2011 but his BABIP remains low at on .267. While hitting only .241, Brown has an OBP of .315 this year thanks to a strong BB%. Also, he is hitting .313 off of lefties (career .223 vs. LHP) so far in 2013 and if he can keep that up, I think we will see Brown emerge as a ray of hope on an old Phillies team that will be rebuilding before long.
Brandon Belt, 1B, San Francisco Giants
Brandon Belt has the most service time of anyone on this list and has had the most success as well. Belt has proven to be a serviceable big league first baseman but he hasn't reached the potential he was touted as having while in the minors. Baseball America stated that Belt's power should be good enough hit "at least 20 home runs a year." He has 17 home runs in 764 career plate appearances. Belt has two things working against him in terms of power production - AT&T Park and a lack of fly balls. Belt sacrificed some power last year in order to raise his batting average and his up the middle approach works well in terms of average (.275 last year) but doesn't work hitting for extra bases. That being said, Belt has lived up to his reputation in terms of being a smart hitter with a good feel for the strike zone. In 2012, he raised his walk rate to 11.4% while lowering his strikeout rate to 22.5%. He is a smart base runner and offers a rare potential for stolen bases at the first base position. If Belt can find a happy medium between his 2011 (.187 ISO) and 2012 numbers and play a full season, we might finally see the 20 home run/ 10 stolen base potential we've heard and read about.