Nitkowski's deal is pending a physical, but he is expected to report to Double-A Binghamton.
Nitkowski, 39, last pitched in the Major Leagues in 2005 with Nationals. That year, he appeared in seven games and allowed three runs in 3 1/3 innings. In ten big league seasons from 1995-2005, Nitkowski went 18-32 with a 5.37 ERA in 336 games and 44 starts.
He was with the Mets in 2001, and allowed no runs in 5 2/3 innings in five relief appearances.
Nitkowski auditioned for the Mets as a sidearm pitcher during Spring Training this past March, but the two sides did not come to terms on an agreement at that time.