When the DBs traded for Randy from the Yankees after the ’06 season, he was coming off a 205 IP season with an ERA of 5.00 but a FIP of 4.27. The trade required an extension for Randy, costing the DBs $26MM for two years of service (between salary and signing bonuses according to Cot’s). 2007 was going to be his age 43 season. Obviously, he was hurt most of the year, but managed to post a good ERA and even better FIP in about 50 innings. In 2008, he pitched 184 innings with both an ERA and FIP in the high 3.00s.

The DBs tend to be a smart franchise, and while they recognized that Randy’s 2006 ERA was too high for skills, they had to realize his age was a risk. Maybe being two years older and having a defined injury two years ago is enough to scare them away. They don’t necessarily don’t want him, but not at the price he was asking. While the Giants’ deal is a base of $8MM, he has something like $4 to $5MM in playing time and performance bonuses. So if he’s bad, the Giants are on the hook for $8MM. If he’s really good again, they’re on the hook for $13MM. It’s not an awesome deal, but defensible.

The league-adjustment is applied to past performance to put all pitchers (both in the AL and NL) on the same scale. After that adjustment, a 3.0 WAR pitcher in the NL showed the same talent and had the same value as a 3.0 WAR pitcher in the AL.

Going forward, that 3.0 WAR pitcher might post a 3.75 ERA as a Giant or a 4.50 ERA as a Ranger, but he’s still the same pitcher with the same value. (Numbers for example only.)

I like Ben Sheets; I agree he has significant value even if he isn’t likely to pitch a lot of innings. And I think he is ideal for a team which needs a No. 2 starter to go with a proven ace. But the Diamondbacks have great pitching in their No. 1 and 2 slots; I can understand the ideal that they want a bottom of the rotation pitcher to soak up innings and save the bullpen. I also think that from a GM’s perspective, there is some disruption costs to using a replacement pitcher for a good part of the year, often in sporadic spurts. Setting aside how good or bad your replacement level pitcher might be, just the sheer act of moving players back and forth between the farm team and the big league team is disruptive. Sometimes other worthwhile players have to clear waivers and be sent down in order to call up the new pitcher. Sometimes players get stuck on the ML roster and can’t be sent down because another team made a waiver claim and the player was pulled back…I have seen that happen with some frequency. How much is it worth to avoid this disruption? I don’t know, but the value isn’t zero. It could make the difference in some cases where the gap between the injury prone candidate and the innings eater is small enough.

This is only true of a poorly run franchise. Replacement-level is definitely for just these purposes — the expected performance of the guy you can find easily for the league-minimum.

Replacement-level IS the fill-in level.