The 27-year-old Waldrop went 0-1 with a 2.53 ERA (21.1ip/6er) in 17 relief appearances with Minnesota in 2012.
He began the season on the 15-day disabled list with a right elbow strain and made four relief appearances with
Class-A Fort Myers before being reinstated and assigned to Triple-A Rochester, where he went 0-0 with four saves
and a 3.34 ERA (35.0ip/13er) in 24 relief appearances.
Waldrop was originally selected by Minnesota in the first round of the 2004 First-Year Player Draft as the 25th
overall pick. He made his Major League debut with the Twins on September 5, 2011 and has recorded a 1-1 record
and 3.62 ERA (32.1ip/13er) in 24 relief appearances during his big league career.
The Pirates now have 18 players coming to spring training as non-roster invitees.