Warning: The following post is current up through Wednesday's games only. An issue deadline yesterday interfered with a more timely posting, but if response is favorable, we can revisit the idea in the future.

Seven Up, Seven Down: The Best And Worst Minor League Teams

Mickey Mantle wore it. Stars like J.D. Drew, Matt Holliday, Joe Mauer, Jose Reyes and Ivan Rodriguez wear it today. Even George Costanza had a thing for the number seven.

Seven also happens to be a good cut-off when stacking up the winning percentages of the 120 full-season minor league teams. To this point, the top seven clubs have compiled a winning percentage of .700 or better, while the stragglers all hover near .300.

The Captains have one of the youngest pitching staffs in the Midwest League, but it's really been the Joe Gardner and Bo Greenwell show in Eastlake, Ohio. Gardner, a righthander taken by the Indians in the third round last year from UC Santa Barbara, has dominated in his first four pro starts, striking out 32 while walking eight over 18 innings. His ground-to-fly out ratio registers at 10.0. Gardner is 22, though, so he might not be long for low Class A. Greenwell has developed much more deliberately. He's 21 and is repeating low Class A, having spent his first two years in the Gulf Coast League. A sixth-round pick in ’07 from a Fort Myers, Fla, high school, he's batting .403/.476/.639 through 19 games and leads the MWL in average, on-base percentage, RBIs (22), hits (29) and runs (20). Oh, and he's also the son of 12-year big league veteran Mike Greenwell.

The Double-A Smokies feature three regulars who sport an OPS north of 1.000: catcher Robinson Chirinos, second baseman/corner outfielder Tony Thomas and shortstop Starlin Castro, the Cubs' top prospect. Castro's warp-speed development continues this season at age 20. Through 19 games, he's batting .370/.416/.593 with a homer, seven doubles, four triples and 18 RBIs. On the pitching side, righthander Andrew Cashner has polished a curveball and changeup to go with his strong fastball. He's gone 1-1, 3.33 and leads the SL with 29 strikeouts in 24 innings.

New Britain's early futility is a bit puzzling when one considers the number of prospects populating the roster. They have an outfield of Joe Benson, Ben Revere and Rene Tosoni, while ’06 first-rounder Chris Parmelee mans first base. Still, the Rock Cats rank last in the EL in runs, home runs (just six), average and slugging. Their pitching staff hasn't been much better—just two EL teams have allowed more runs per game than has New Britain. But a rotation featuring David Bromberg (17-4 K-BB in 18 IP), Deolis Guerra (zero walks in 18 IP), Carlos Gutierrez (16-6 K-BB in 19) and Tyler Robertson (3.18 ERA) probably will thrive in time, if given solid defensive support.

Power Index

MLB Advanced Media, our statistician, provided a nifty new tool for us to play with this season. We can now filter category leaders by date range, either by league or by classification. So if we want to find last week's home run leader in the Midwest League, well now we can. The answer: first baseman Jerry Sands with five for Great Lakes. Likewise, we can quickly discern that Northwest Arkansas righty Aaron Crow, with six, issued the most walks among Double-A pitchers last week.

So as I thought of ways to apply this new tool in a meaningful way, I hit upon the idea of a power index—or something that would measure recent performance of Triple-A players and hint at which of them may be in line for a big league callup, if the stars align. For the first test run, I settled on isolated power for batters and strikeout rate for pitchers, each measured over the past 10 days, to capture a snapshot of the best performers. After all, what gets more attention than extra-base hits or strikeouts?

Here, we're placing triples on equal footing as doubles so as not to skew the results toward fast players, and we're using strikeouts per batter faced for pitchers, so that high-walk hurlers don't benefit on account of more strikeout opportunities. Also, Triple-A players are separated along league lines. The offensive contexts are so different that we need International and Pacific Coast leaders.

Ah yes, it's nice to be young and in Las Vegas. Wait, just four of those games took place in Vegas, you say? True, but the remainders took place in Salt Lake and Colorado Springs. And on to the pitchers . . .