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Source: Pirates, Grilli agree to deal
The deal, which is pending a physical, could give the Pirates the flexibility to trade closer Joel Hanrahan and use Grilli in a ninth-inning role.
Grilli, 36, emerged as one of the most reliable setup men in the National League last season, averaging nearly 14 strikeouts per nine innings and producing a 2.91 ERA.
Hanrahan could earn approximately $7 million in arbitration, and the Pirates have discussed trading him for a comparably priced starting pitcher, sources say.
Grilli's agent is former major leaguer Gary Sheffield.