The Sutton/Slaten exchange was expected, since the Pirates claimed Sutton a couple days ago and had an extra man in their 'pen thanks to another series of transactions earlier this week.
Fryer joins the team because Rod Barajas suffered a minor injury in Monday's game. It appears that Barajas won't need to go to the DL, but the Pirates probably don't want to use him today, and can use a backup to Michael McKenry. (Casey McGehee is the Pirates' emergency catcher.) Fryer will presumably be sent back down as soon as Barajas is healthy to play. The Pirates can probably also clear Fryer from the 40-man roster whenever they feel like it, as well -- he's having a miserable season in Indianapolis, and it's unlikely anyone would claim him.
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