In 2011, Jason Grilli was pitching for Class AAA Lehigh Valley in the Philadelphia Phillies organization.
During parts of two seasons with the Pirates, Grilli, a free-agent reliever, turned himself into a sought-after commodity. On Monday, he decided to return to Pittsburgh.
Grilli and the Pirates agreed to terms on a two-year, $6.75 million contract, according to a source. Grilli must pass a physical before the contract becomes official.
Fox Sports first reported the agreement.
By bringing Grilli, 36, back, the Pirates expanded their relief options and retained a potential closer in the event that they trade Joel Hanrahan. Other teams have expressed interest in Hanrahan, who will be a free agent after the 2013 season.
Hanrahan is eligible for arbitration for the final time this winter and will earn in the neighborhood of $7 million, and the Pirates might not want to commit such a large portion of their payroll to two relief pitchers.
The new collective bargaining agreement requires teams to make one-year qualifying offers of roughly $13 million to free agents if the team wants to receive a compensatory draft pick when the player signs with another team, making it almost certain that the Pirates won't receive draft pick compensation if Hanrahan leaves after 2013.
In parts of two seasons with the Pirates, right-handed Grilli struck out 127 in 911/3 innings with a 2.76 ERA. He had a spectacular season in 2012 as a setup man, striking out 13.8 batters per nine innings. He earned $1.1 million in 2012.
Grilli's performance declined somewhat in the second half of 2012. He allowed 12 earned runs in 25 innings after allowing only seven earned runs in 332/3 innings in the first half.
Grilli joined Hanrahan, Tony Watson and Jared Hughes as current members of the bullpen. Justin Wilson, Chris Leroux and Bryan Morris also are candidates to make the active roster as relievers.
Speaking at the winter meetings last weed, Pirates general manager Neal Huntington said his club was "in the mix" for Grilli and was hopeful that he would return.
"We feel like we made a very fair offer to Jason and we sure hope that it keeps him in a Pirates uniform," Huntington said. "Our hope is that he continues to mentor young pitchers and continues to strike out hitters at a quality rate for us."
The Pirates signed Grilli in July 2011. He was pitching in the minor leagues for the Phillies organization at the time after missing the entire 2010 season due to injury.
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