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Pirates add pieces for stretch drive
The Pirates are last in the National League in OPS from their right fielders, and Buck will provide a veteran backup to Russell Martin with Michael McKenry out for the season after undergoing surgery on his left knee.
Byrd is batting .285 with an .848 OPS and 52 extra-base hits in 425 at-bats.
The Pirates, who also get cash in the deal, will send minor league infielder Dilson Herrera and a player to be named to the Mets.
A native of Colombia, Herrera, 19, has played 163 games at second and 59 at third in minors. He has a .751 OPS in the Class A Sally League.
The Pirates are seeking their first winning season and first playoff berth in 21 years.