Shaun Marcum hasn't pitched since June 14 against the Royals, and the Brewers were concerned. Todd Rosiak:

The good news about the sore right elbow bothering Shaun Marcum is that there doesn't appear to be anything structurally wrong.

The bad news is the possibility remains he might wind up on the disabled list because the injury-plagued Milwaukee Brewers are in serious need of some rested arms in their bullpen.

That possibility has turned into reality:

#Brewers RHP Shaun Marcum has been placed on the 15-day DL, retro 6/15, with right elbow tightness. 1B Travis Ishikawa has been reinstated.

— Mike Vassallo (@MikeVassallo13) June 23, 2012

This goes a long way toward explaining why the Brewers signed Livan Hernandez on Friday; he can provide some of that bullpen assistance. Who's going to take Marcum's spot in the rotation? Rosiak again:

The Brewers have penciled Marco Estrada back into their rotation for a start Tuesday at Cincinnati, and they also have Mike Fiers on hand for the time being in case Marcum is forced to miss another start.

Estrada himself has been on the DL since a groin strain running the bases on May 23 against the Giants. This isn't the way the Brewers had planned to defend their 96-win division title year; they're currently fourth in the NL Central, four games under .500.

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