Tim Laudner hit 42 homers with 104 RBI at Double-A in 1981.
He hit 77 homers in his big-league career.

Ken Phelps went .333-46-141 at Triple-A in 1982.
He went on to bat .239 with 123 homers in the big leagues.

Russell Branyan went 40-106 and 39-105 in 1996 and 1997 at Single and Double-A.
He never had 80 RBI as a big leaguer and had just one season of 26 homers.

Rick Ankiel was the 1999 Baseball America Minor League Player of the Year.
He lasted 242 big league innings before having to quit pitching to become a hitter.

Jon Rauch was the 2000 Baseball America Minor League Player of the Year.
He was moved to the pen in the bigs and posted a 4.00 ERA with no All-Star births.

Jeremy Hellickson was the 2010 Baseball American Minor League Player of the Year.
He’s gone 61-58 with a 3.90 ERA, 1.25 WHIP and lots of general averageness.

As should be clear from the small list of players above, minor league dominance doesn’t always lead to major league success. The above names are not cherry-picked either. The history of the game is littered with minor league superstars. Looking for more recent examples? Take a look at the first season efforts of Mike Trout (.590 OPS in 40 games), Edwin Encarnacion (.232 with nine homers in 69 games), Adrian Beltre (.648 OPS in 77 games) and Byron Buxton (.576 OPS over 46 games). Hell, take a gander at Clayton Kershaw’s first year effort (5-5, 4.26 ERA, 1.50 WHIP, 4.35 BB/9 over 107.2 innings). It just ain’t easy folks, even for the elite talents in the game.

The issues with transitioning the numbers from the minors to the majors are many. A few that come to mind include:

1 - How do the minor-league parks play? Are they hitter or pitcher-friendly?

2 - How many parks in the league the player is in are hitter/pitcher-friendly? Is the lighting good? Is the field in solid shape? How is the umpiring? Is it up to par or lacking?

3 - What is the level of competition? A first-round pick out of college should be able to hammer pitches from an 18-year old who went to his senior prom three months earlier. Is a 19-year old hitter trying to get base knocks off a 28-year old veteran who might lack elite skills but certainly knows how to work the count against a young, undisciplined hitter? The minors are full of players ranging from pre-drinking age youngsters to guys in their 30’s. Some of the players are elite level skills-wise. Others are merely warm bodies; organizational depth if you will. The talent level, at all levels of the minors, vacillates substantially.

4 - Let’s talk about goals for a moment. The next future star, let’s call him Frank-the-Ace-To-Be,  throws the ball 97 mph with that hellacious slider and is going to be performing in a big league ballpark in the very near future. He knows it. You know it. The organization knows it. Doesn’t matter if he posts a 1.91 ERA or a 3.91 ERA, at some point in the near future he will be called up to the majors. Given that fact, there is less pressure on Frank-the-Ace-To-Be to perform. Everyone knows his first two pitches are elite. So the goal is for him to refine the changeup up, his third offering. Frank doesn’t need to strike every batter out to earn a promotion. Therefore, he throws the changeup more frequently than he ever would in the big leagues to try and get a “feel” for the offering. The pitch isn’t very good either so he gets hit hard on that change. But it’s an improving pitch. He’s learning. He’s preparing for the big leagues. So Frank has that 3.91 ERA and batters are hitting .284 against him. If he stopped throwing the change and only went with his two elite pitches, the numbers could easily drop to 2.81 and .244. How different were your opinion be of Fran if the numbers changed like that?

Frank doesn’t need to worry about the results as much as Jimbo does. Jimbo needs to hit homers and produce extra base hits or he’s going to be stuck riding buses for the rest of his life. Jimbo faces Frank and goes 3-for-4 with a homer. Jimbo just lit up Frank-the-Ace-To-Be. That looks good, Mr. Minor League ripping up the next big league ace. You read that and think – Jimbo is ready. But is he? The context is that Jimbo’s team was behind 11-1 after the second inning so Frank was giving plenty of room to work on his changeup with no worry about losing the game. Turns out that Jimbo struck out in the first inning on the slider but the next three times up he got hits on... the changeup. It’s not that Frank is stupid, he knows that Jimbo is ripping his change, but Frank isn’t worried about the game this Tuesday. He’s worried about honing his changeup so he can get out Andrew McCutchen.

The point is that players are tasked with working on different things when in the minors. As a result, the statistics aren’t always indicative of the level of performance of a player. Gotta keep that in mind when you’re attempting to assess the numbers.

5 - There are the unknowns as well. How will Frank handle the pressure of 55,000 cheering fans? Will Frank cower at the pressure like Willie Mays did when he was first promoted? Will Frank be seduced by the power of the Dark Side and end up whoring around, boozing til all hours of the night, as the hotties throw themselves at him? I’m in my 40’s and that sounds appealing to me. I can only imagine what I would have done if I had the chance to do that at 22. Will Frank “press” if he starts out slowly? Will that result in some horrible production? While riding buses from town to town is nice, will it be far too overwhelming to be staying in a hotel, in a new state, week after week for Frank? How will he deal with having six cameras in his face after every game with reporters trying to follow him into the shower to get a scoop? Minor league success or not, there is really no way to know how any player will perform in the bigs, especially early on in the process.

6 – The best talents don’t often spend a lot of time in the minors making it hard to gain a large enough sample size to draw any substantial conclusions. Many of them are called to the big leagues without ever seeing time in Triple-A. In fact, some talent evaluators believe that there is better talent at Double-A than Triple-A. Moreover, should be pointed out that most think the jump from Single-A to Double-A is the toughest transition to make since Triple-A is filled with a lot of veterans who are hanging on for a paycheck or fellas who are AAAA types (not successful enough for the majors but always successful in the minors).

So, as you can see, looking at all the concerns it should be clear that merely reading minor league numbers for players doesn’t come close to explaining the entire story of who the player is or will becomes.

If you want to try something official/analytical in an attempt to get a handle on things...

An attempt to figure it all out was famously put together by Bill James with his Major League Equivalents (known as MLE’s). James tried to create a scientific system to directly translate minor league numbers into big league numbers. What does a .275 batting average in Double-A mean? How do we translate that 3.38 ERA at Triple-A? The theory of MLE’s is that we can translate the level of statistical performance in any minor league to the majors. The conversion seems to be more successful the higher one progresses in the minors meaning that Single-A numbers are tough, Double-A numbers are a bit better and Triple-A numbers give us the clearest picture when trying to project out minor league success. You can read more about MLE’s HERE and HERE if you would like to continue on with this discussion.