The Pirates have shipped Doug Slaten and Matt Hague to Indianapolis, Dan Potash says. Slaten we expected, with a spot needed because Drew Sutton will join the team today. I'm not yet sure what's going on with Hague, but there were reports earlier today that Eric Fryer was in Pittsburgh because of Rod Barajas' injury. It wasn't clear whether Fryer would actually join the team or whether that was just a precaution. It doesn't look like Barajas will go to the DL, but the Pirates might want Fryer there today if Barajas is unavailable.
UPDATE: Yeah. Fryer and Sutton have joined the team. I imagine Fryer won't be in Pittsburgh long. The Pirates will have to make space on the 40-man for Fryer, so there should be another move coming.
UPDATE from David: Charle basically had this all correct, but there is some confusion in the comments. Both Matt Hague and Doug Slaten have been optioned to Indy. Yes, Slaten does have an option and the Pirates have said he was optioned, not DFA'd.
Fryer was DFA'd for assignment last year and taken off the 40-man roster. As WTM noted in the comments this means that Pirates have to make another move to clear space for him on the roster. As he also pointed out, the reason they activated Fryer and not Morales is that whoever came up is most-likely going to get DFA'd in just a couple days and Morales might not clear waivers, while Fryer most certainly will.
The other moving piece is that Chris Leroux will come off the 60-DL shortly and when Fryer is designated for assignment he may take the place on the 25-man roster. This may then lead to another pitcher being DFA'd. If that is the case, another position player would have to come up to effectively replace Matt Hague because he won't be available to be recalled for ten days. Jeff Clement could be a choice because the 40-man spot would be available, otherwise it is one of the usual suspects. Got it?
UPDATE: In creating the 40-man roster spot for Eric Fryer the Pirates have designated Daniel Moskos for assignment. While some are surprised because of Moskos' 4th overall draft status, it really was a choice between him and Daniel McCutchen. Charlie has created a separate post for the news.