The Pirates made official this afternoon a one-year contract with right-handed pitcher Jeff Karstens.
The deal is worth $2.5 million plus performance bonuses, according to a source, and was pending a physical, which was completed Thursday.
Karstens, 30, made 19 appearances last season, going 5-4 with a 3.97 ERA. But he was limited by injury as he twice appeared on the disabled list.
To make room on the 40-man roster, the Pirates designated right-handed pitcher Zach Stewart for assignment. Stewart was acquired in November in a trade that sent minor league pitcher Kyle Kaminska to the Boston Red Sox.
Michael Sanserino: email@example.com, 412-263-1722 or on Twitter @msanserino.