Roster Advice -- Sexy Rexy, baseball edition

A traveling theater troupe is staging Rent. The actor who plays Mark has to miss a couple performances, and they put on the backup. No matter how the backup does, the initial actor will have the role of Mark when he gets healthy.

A traveling theater troupe is staging Rent. The actor who plays the singing waiter at the diner has to miss a couple performances, and they put on the backup. The backup nails it.

And now, the backup has the role.

Look, when Troy Tulowitzki got hurt last year, Josh Rutledge took over, and he was good. In a small sample, he was actually really good. But when Tulo got healthy, he got his job back. Part of that was the fact that Rutledge was never really that good to begin with, sure, but it's also because Tulo is...well, he's the Mark, or Collins, or another one of the Rent leads.

Rafael Betancourt is not a lead character. Precious few closers are. So keep an eye out while he is out (for what looks to be a short-term absence) with injury, because the Rockies have a reliever who has so far in 2013 earned a 1081 ERA+. Yes, that is a four-digit number, and no, I didn't think that was possible, but Rex Brothers has been insanely good so far.

In 21.1 innings, 84 batters, Brothers has given up one run to go with 21 strikeouts and eight walks. No, he's not a true 0.42 ERA guy, but in three seasons - all in Colorado - his career ERA is 2.98, and his career ERA+ is 155. A large part of that (including his insane this-year numbers) is due to the Coors Field ballpark corrections, but still -- the dude can pitch.

Odds are, Brothers pitches fine while Betancourt is out, however long that ends up being. Odds are, he's good, but not actually spectacular, and Betancourt gets his singing-waiter job back in due time.

But closers aren't the lead. At least, closers who aren't named Rivera or Kimbrel or Papelbon aren't the lead. Closers named Betancourt certainly aren't the lead. If Brothers understudies his way into a couple no-baserunner, multi-strikeout saves, what's stopping Walt Weiss from letting him keep the job?

Or maybe Betancourt gets his job back, and the Rockies, realizing that they are exceedingly unlikely to contend all year long, deal him to the highest bidder, and Brothers gets the job that way. I don't know, but it seems silly to me that a pitcher who has pitched as well as Brothers has for three seasons now, who seems likely to get his team's next save opportunity or two, who has a name as genuinely old-Westy cool as Rex Brothers is owned in only 17% of Yahoo leagues.

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