If you get statheads together for very long, eventually you'll hear the words "replacement level." Generally, what they're referring to is a fictitious player, someone who isn't quite good enough (or just barely good enough) to play Major League Baseball, and is "freely available" to your team if someone gets hurt.
That's all well and good, but there aren't very many players right at replacement level, and even when there are, it's not easy to tell which one (Ben Hendrickson? Zach Jackson?) will perform up to that level. In the starts that Ben Sheets and Tomo Ohka missed earlier this year, their replacements combined for one win below replacement level.
On the flip side, Doug Melvin has displayed that, once you lose a player or two for a season, you don't have to settle for the Chris Barnwells of the word as your replacements. In this case, with a deep bench and flexible management, replacement level might accurately be set much higher. David Bell wasn't "free"--he is costing us $2 million for the rest of the season (and a throw-in minor leaguer), but despite Philadephians protesting to the contrary, he's much better than some Triple-A scrub.
I ran some numbers to see how Brewers infield replacements have fared in total compared to the people they're replacing. The lines for Bell, Graffanino, and Hall are their season totals--they may give a good indication of what type of production we'll get from these positions for the rest of the season.
SECOND BASEMEN | THIRD BASEMEN | SHORTSTOPS | |||
Rickie Weeks | 279/363/404 | Corey Koskie | 261/343/490 | JJ Hardy | 242/295/398 |
Other Brewers | 226/261/321 | Other Brewers | 331/392/523 | Other Brewers | 246/310/492 |
Tony Graffanino | 270/343/397 | David Bell | 275/342/395 | Bill Hall | 272/327/565 |
It's a little tough to parse these numbers--especially since Graffy and Bell have been with the Brewers for such a short time, and because Bill Hall is part of all three sets of "Other" numbers. However, it gives you a clue that losing 3/4 of the infield might not be as bad as it was cracked up to be.
Sure, we'd like to have Rickie, JJ, and Koskie back, but with replacements like these, who needs starters?