It’s a bit early to tell, but an erstwhile reliever named James McDonald appears to be credible in his new role as (at least) a back-end starter. He pitched six scoreless innings with four strikeouts against the Colorado Rockies, good for a quality start.

He won’t always be this good. But he won’t have to be because last night he was very, very good.

Granted, the Colorado Rockies aren’t exactly the National League’s best team, at least not this year. But, Colorado is a team that has given the Pirates trouble in the past, and one that the Bucs will have to beat if they are going to amount to anything.

McDonald got the job done last night, and in a big way. That is to say, most pitchers don’t do anywhere near this well against the Rockies, or even against the Pirates. The result was a 5-1 victory with the sole run given up in the eighth inning by Sean Gallagher.

The Pirates got McDonald by trading closer Octavio Dotel for the supposedly inferior reliever whom they’re trying return to the starter role (plus outfield prospect Andrew Lambo). If they succeed, the Pirates will have come out way ahead on the deal, regardless of what Lambo does or doesn’t do.

The reason this could happen is because closers are generally overvalued in the baseball marketplace. During his tenure as a reliever with the Pirates, Dotel was middling at best. His 4.28 ERA was worse than that of Evan Meek, Javier Lopez, Joel Hanrahan, and DJ Carrasco.

But Dotel had the advantage of being a “closer,” which is to say that he had the term “save” attached to his name. He was credited 21 of them in a little more than half a season, versus two for all other Pirate relievers thus far. That’s something most managements will trade for—even to the point of giving up a potential starter.

Starters are more valuable than relievers for one reason—they pitch more innings during a game, and even over a whole season.Therefore the ERAs of a starter and reliever aren’t really comparable. The fact that a reliever is a closer doesn’t change this fact.

Almost anyone in the Major Leagues can pitch well for one, maybe two, innings at a time. What separates the men from the boys is how well a starter holds up during a sixth and seventh inning of a game (and sometimes beyond), when he is getting tired and most likely to give up runs.

It’s what I call a “last inning” problem that leads to a lot of runs being given up in those innings. (The worst relievers’ “last inning” problem starts from the moment they take the ball.)

A “save” situation is one where a team hands the ball to a closer and tells him, “We’re handing you a lead, just don’t blow it.” Usually he doesn’t, and the team wins. Of course, if a closer does lose the lead, it’s called a “blown save.”

Paradoxically, a closer can sometimes “win” a game in this way. He blows another pitcher’s lead in the top of the ninth, his teammates regain it in the bottom of the inning with a walkoff, and the closer is the pitcher of record. He is awarded the win even though he did more to lose the game than to win it.

The recent trade is reminiscent of the 2008 exchange of reliever Damasco Marte for starter Ross Ohlendorf (in effect). With the other three players (Jeff Karstens, Dan McCutchen, and Jose Tabata) together easily worth Xavier Nady, the Bucs made out very well in that deal.

The Pirates appear to have made a science of signing, trading for, and “Rule 5-ing” potentially good relievers. When they pan out, they are then re-traded for other players the Pittsburghers need. It’s one of the few things that they seem to do well.

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