Four exciting, young outfielders broke out into the prospect spotlight in 2006: Fernando Martinez, Jose Tabata, Carlos Gonzalez and Andrew McCutchen. The 2007 season has been another matter entirely, though. Each member of that foursome has disappointed to some degree and failed to capitalize on their rising stocks.

Before the 2007 minor league season began, McCutchen (13), Gonzalez (18), Martinez (22) and Tabata (27) were all ranked among the top 30 prospects in all of baseball by Baseball America. It is possible that all four, by the end of the season, will slip further down the chart while other prospects take their places among the elite.

But the question is: Just how far have these four players fallen? Are their seasons really as bad as some think, or is it just a matter of unreasonable expectations by impatient fans and media? I'm going to outline the players and give a few of my thoughts and then I would like to hear from as many members of the Baseball Analysts' community as possible; let us know which of these players, if any, are going to be superstars and why.

Andrew McCutchen | Pittsburgh Pirates
Bat/Throw: R/R
HT/WT: 5-11/175
Born: 10/10/1986
Birth Place: Fort Meade, Florida
Acquired: 1st round, 2005 (11th overall)

       AVG   OBA   SLG   AB  HR  SB  BB%    K%
2006  .291  .356  .446  453  14  22  8.5  20.1
      .308  .372  .474   78   3   1  9.3  25.6
2007  .235  .296  .349  289   4  11  8.0  19.4

It has been a long time since the Pirates had a hitting prospect with the potential of McCutchen. As a result, Pirates fans are eager to see McCutchen take to the big stage, but it will happen a little slower than expected. After a hot start last season, McCutchen made the rare leap past Advanced A-Ball and acquitted himself well with a late-season promotion to Double-A, albeit in only 20 games.

This year, however, McCutchen has struggled to hit for average and his slugging percentage is down about .100 points. He has struggled this season against right-handed pitchers and is batting only .214/.278/.282 against them. McCutchen is also batting only .200 on the road. On the plus side, he is not striking out more frequently than he did last year and he has been walking just about as often.

Another encouraging sign is that McCutchen's average has risen with each month, from .189 in April to .230 in May to .266 in June. Baseball America lauded McCutchen's attitude, maturity and passion for the game in a pre-season scouting report, so chances are good that 2007 is simply a growing pain, and/or a byproduct of being rushed by an organization desperate for a home-grown superstar.

Truth be told, McCutchen should probably just be reaching Double-A right about now... And hopefully no damage has been done. I expect McCutchen to be close to a five-tool player, and have the potential to be a Curtis Granderson type of player.

Carlos Gonzalez | Arizona Diamondbacks
Bat/Throw: L/L
HT/WT: 6-1/170
Born: 10/17/1985
Birth Place: Maracaibo, Venezuela
Acquired: Undrafted free agent 2002

       AVG   OBA   SLG   AB  HR  SB  BB%    K%
2006  .300  .349  .563  403  21  15  6.9  25.8  
      .213  .294  .410   61   2   1 10.3  19.7 
2007  .253  .283  .428  285   9   5  4.0  22.1

Gonzalez was voted as Baseball America's third best prospect coming in to 2007, right behind fellow outfielders Justin Upton and Chris Young. Young is establishing himself in the majors, albeit with some growing pains of his own, and Upton has recently joined Gonzalez in Double-A, after having torn up Advanced A-Ball.

Not surprisingly, Gonzalez' performance has improved with the arrival of Upton. It is tough to get a really good read on D-Backs' hitting prospects because they play in some very good hitting parks. Gonzalez' breakout 2006 took place in Lancaster, which is one of the best hitting parks in minor league baseball and it has distorted many a stat line. Mobile is a fairly good hitting park too (Gonzalez is hitting .241/.272/.399 on the road), although it is not quite as prolific.

One of the biggest problems with Gonzalez' season - beyond the .135 drop in slugging percentage - is his reduced patience at the plate. His walks are down almost three percent, from 6.9 in Lancaster in 2006 to 4.0 this season. He is also in danger of being labeled a platoon player if he cannot improve upon his .165/.184/.239 line against left-handers.

Other knocks against him are his size (he is projected to be a below-average runner in a couple years), his propensity to swing for the long ball and his occasional lack of hustle, which led to a benching last season. His biggest value is his plus arm in right field. Based on his hitting environments, I believe the ceiling for Gonzalez' future has been set too high and he will top out around 25 home runs in his prime.

Fernando Martinez | New York Mets
Bat/Throw: L/R
HT/WT: 6-1/190
Born: 10/10/1988
Birth Place: Rio San Juan, Dominican Republic
Acquired: Undrafted free agent 2005

       AVG   OBA   SLG   AB  HR  SB  BB%    K%
2006  .333  .382  .505  192   5   7  7.2   18.8
      .193  .232  .387  119   5   1  4.8   20.2
2007  .271  .328  .377  236   4   3  7.8   21.6

At 18 years of age, you have to be really, really impressed that Martinez is holding his own in Double-A, even if some people feel he hasn't truly impressed. Personally, for me, there not a lot to dislike, although his walks are a little low and his strikeouts are a little high - especially for the modest power displayed in 2007.

But you have to keep going back to the age. You also have to look at the park factors for his home park in Binghamton and realize that it significantly retarded power numbers (0.54) between 2004-2006, according to Baseball Think Factory.

With a line against left-handers of .259/.306/.362, the left-handed batter has done OK in that regard. Martinez has only had one really good month this season and May .324/.387/.426) was sandwiched between two lackluster performances. Martinez, like McCutchen, may be suffering from a little bit of over-anxiousness by his parent club. He was promoted to Double-A in 2007 - due to a strong spring showing - despite hitting only .193/.254/.387 in 119 Advanced A-Ball games.

I like to look to Toronto Blue Jays' outfielder Alex Rios, who was recently named to his second straight All-Star game, as a perfect example of why there is no point in getting up-in-arms over young players' power numbers. Rios did not slug over .354 in his first three pro seasons (ages 18-20). He topped out in the minors at Double-A at age 22 with a .521 slugging percentage but then regressed to slug below .400 in his first two MLB seasons.

During Rios' first four MLB seasons, his homer totals were: 1 (in 426 at-bats), 10 (in 481), 17 (in 450) and 17 (in 328 at-bats so far this season). Rios is on pace to hit more than 30 homers in 2007, a far cry from 2004 and 2005 when fans were screaming for the Jays to trade him. Those same fans now call Rios untouchable.

If young prospects show the ability to hit for average with some semblance of patience and a good batting eye - be ecstatic, even if some scouts are less than enthralled with Martinez' season and expect him to be move out of centerfield. Reports say he has a willingness to hit to all fields and has solid strike-zone awareness for his age. Keep in mind this kid is also just learning to speak English and is adjusting to life in North America on the fly.

Jose Tabata | New York Yankees
Bat/Throw: R/R
HT/WT: 5-11/160
Born: 8/12/1988
Birth Place: Anzoategui, Venezuela
Acquired: Undrafted free agent 2005

       AVG   OBA   SLG   AB  HR  SB  BB%    K%
2006  .298  .358  .420  319   5  15  8.6  20.7 
2007  .305  .368  .378  262   2  11  9.0  17.6

Tabata is the only player of the four who has yet to exit A-Ball and that is probably a good thing in the long run. He has only two homers on the season, but the 18-year-old prospect is hitting more than .300, while also lowering his strikeouts and raising (slightly) his walk percentage.

Tabata has hit both left- and right-handed pitchers well this season. Truth be told, he has been scorching lefties with a line of .347/.410/.453. He is also hitting equally well on the road and at home, in a league that is often considered a pitcher's league. Tabata has shown improvements each month, with his average going from .294 in April to .299 in May to .346 in June.

Another encouraging sign is that his strikeout totals have improved each month. He began the season by striking out 21 times in 85 at-bats. In May, he lowered his strikeouts to only 15 in 105 at-bats. Then in June, he kept it up with 11 strikeouts in 78 at-bats. A positive sign for his future career as a run producer, Tabata's batting average has risen significantly this season with men on base (.312), as well as with men in scoring position (.357).

Applying the Rios factor to Tabata, I see absolutely no reason for anyone to sour on his season, or his future career. The power should develop, and even is it doesn't, I see enough positive signs to believe he will be a productive major league baseball player, especially if he can keep in shape and stay motivated.

OK, you've heard my thoughts and now it's time time to express yours: Which one of these four outfielders will be the most productive MLB player? Do you smell a bust with any of these guys? Post a comment or e-mail me.