6. Minor League and Major League Stats

[This is a continuing series that will run periodically throughout the 2005 season. Start here for full details.]

Let’s look at the average minor-league stat lines (through 1995) for each of the different grades assigned by John Sickels in his 1996 Minor League Scouting Notebook. To save space, I’ve only included rate stats here.

Minor League Stats

Prospects in the Grade A group had the highest batting average, on-base percentage, and slugging percentage. They walked a little more than average, and struck out a lot more. One thing that doesn’t show up in the chart above is the fact that they hit an unusually large number of triples. This is due primarily to Bobby Abreu (50 triples, 1952 at-bats) and Johnny Damon (44, 1599).

Members of the A- group had the best ERA, were hardest to hit, and allowed the fewest walks. The Grade A group struck out the most batters. Generally speaking, the pitchers with the higher grades were harder to hit and struck out more batters than those with lower grades. Interestingly, there was very little difference from top to bottom in terms of home run rates.

Major League Stats

Players in the A- group have the highest batting average, on-base percentage, and slugging percentage. Five members of the A- group have batting averages above .300 (minimum 2000 at-bats: Vladimir Guerrero, .325; Nomar Garciaparra, .322; Jason Kendall, .306; Mike Sweeney, .305; Shannon Stewart, .303), whereas only two members of the A group do (Derek Jeter, .315; Abreu, .307). [Note that Garciaparra's batting average has dropped 10 points from .332 since the conclusion of the 2001 season.]

The on-base percentages of the A and A- groups are almost identical. Each group has three representatives among the top 10 (Grade A: Abreu, #2, .408; Jeter, #5, .385; Scott Rolen, #7, .378; Grade A-: Guerrero, #3, .390; Kendall, #4, .387; Sweeney, #8, .377). [Guerrero has moved from #9 to #3 on this list since the initial study. Sweeney has bumped Garciaparra out of the top 10.]

One interesting change from the initial study is the shift in distribution of slugging percentages. From 2002: “The two highest slugging percentages belong to members of the A- group (Guerrero, .587; Garciaparra, .570), while the only two Grade A players to make it into the top 10 are Abreu (#5, .522) and Rolen (#7, .508).”

Now, there is an even split among members of the A group (Abreu, #5, .522; Rolen, #6, .520; Andruw Jones, #10, .493), the A- group (Guerrero, #1, .589; Garciaparra, #3, .549; Sweeney, #7, .498), and the B group (Giles, #2, .550; Richie Sexson, #4, .528; Trot Nixon, #9, .496).

Every group on the whole became less patient at the plate upon reaching the Show. All but the A-, B, and C groups struck out more as big-leaguers. Members of the A- group made much better contact at the highest level (.110 K/PA) than in the minors (.146 K/PA). The A- group also is the only one to significantly improve its BB/K (.661 in minors, .757 in bigs).

Every group in the study had better raw power numbers in the big leagues than in the minors. The C+ and C- groups improved their numbers the most (jump from .146 to .167 ISO and .318 to .353 XB/H for the former, .119 to .133 ISO and .273 to .307 XB/H for the latter). The B group saw its power improve the least (.147 to .150 ISO and .308 to .329 XB/H).

As with the minor league numbers, and again not showing up in the chart, players in the Grade A group have hit a disproportionate number of triples. Damon (74 triples, 5553 at-bats), Jeter (42, 5513), and Abreu (41, 4140) are largely to blame.

In the original study, the gap between the best group (B+) and second best (A) was pretty large in terms of ERA (4.12 to 4.66). The gap has narrowed considerably (4.20 to 4.31), thanks in large part to the emergence of Jason Schmidt and the very sharp declines of Chan Ho Park and, to a lesser degree, Danny Graves and Dustin Hermanson.

The B+ group has been toughest to hit, the B group the easiest. The A group has the lowest home run rate, the B group the highest. The C group has walked the most batters, while the A group has fanned the most and displayed the best overall command.

Unlike the hitters, only one group has shown improvement in any statistical category on reaching the big leagues (the C+ group dropped its walk rate from 3.73 to 3.45 per 9 IP). The C- group has shown the least amount of degradation from minors to majors in terms of ERA (3.83 vs 4.82), the C group in terms of H/9 (8.47 vs 9.28) and strikeout rate (7.19 vs 6.58 per 9 IP), and the A group in terms of HR/9 (0.56 vs 0.98).

Overall, the pitching prospects have had much worse numbers at the big-league level than in the minors:

Next time we’ll check to see what, if any, characteristics players who have become big-league stars share. Until then, enjoy!