Astros to use piggybacking system at all minor-league levels

This isn't Pirates-related, but I thought the Astros' new plan for all their minor-league levels (including Triple-A) was interesting and warranted discussion here.

The Astros will employ a tandem “piggyback” starting rotation at all levels of their minor-league system in 2013 ...

“Pitchers who pitch well get the same amount of innings as they would get in a five-man rotation,” Luhnow said. “It enables you to guarantee all eight of those starters innings. … What happens in a five-man rotation a lot of times is middle relievers get a whole lot of innings. And we feel like these eight starters at all four of our full-season (minor-league) levels are the priority to get the innings.” ...

“The primary purpose is to allocate your innings to your starters and not limit it to your starters,” Luhnow said. ...

“The person that starts the game the first time around will … not start the game the second time around. So in other words, group one, the starter will either go five innings or 75 pitches, whichever comes first. The second starter will go four innings or 60 pitches, whichever comes first.”

There are a couple issues here. One is health, which I don't think the Pirates should be overly concerned about, since they're already doing a pretty good job keeping their minor-league pitchers healthy. The other is distribution of innings. The Astros' plan allows more of their pitchers to work on a schedule, and it allows high-priority arms to get lots of innings. It's pretty common for teams to do this at the lower levels, but also doing it at the high ones is an interesting idea. We'll see if it catches on. The one downside I can think of offhand is that it might make NRI-type relievers -- guys like Mike Zagurski, say -- less inclined to sign with teams pursuing this strategy.

Rudy Owens will be of the Astros' starters at Triple-A, by the way.