Byrd hit a career-high 24 homers this year for the New York Mets and Pittsburgh.
The 36-year-old outfielder was acquired by the Pirates on Aug. 27 and hit .364 in six postseason games, with one homer and five RBI. He batted .291 during the season and had 88 RBIs, one short of his career best.
Byrd was suspended for 50 games in 2012 following a positive test for a drug that can reduce side effects of steroid use and increase testosterone. At the time, Byrd said he mistakenly used the medication for a recurrence of a condition that earlier required surgery. He says he did not use it for performance enhancement.