The 32-year-old hurler will test the open market after being removed from the 40-man roster and declining an outright assignment to the minor leagues.
In losing the journeyman reliever, the Mets part with someone who has “some strikeout ability” and who “can be tough on left-handed hitters,” per The Sports Network.
The southpaw made 13 relief appearances for New York in 2012 after spending the majority of the season with Triple-A Buffalo. In 10 innings, he posted a 1.80 ERA while allowing six hits and five walks.
The Illinois native initially joined the Mets in late June and appeared in three games before being demoted to the minor leagues, where he spent most of July and all of August. He returned to the big leagues in September when the rosters expanded.
In 51 games with the Bisons, he was 4-3 with a 2.33 ERA. He finished second on the squad in appearances and, among pitchers with at least 30 innings of work, he had the best ERA.
Originally signed by the Mets as a free-agent in February of last year, Hampson spent all of 2011 in the minor leagues, pitching for Buffalo and going 3-3 with a 3.41 ERA in 52 games. He was granted free agency following the season, but was re-signed for 2012.
Prior to playing in the Mets organization, he pitched in the unaffiliated, independent Atlantic League. He previously pitched at the major league level for the Colorado Rockies and San Diego Padres from 2006-08.