Humber, 26, has spent the past two seasons in the Twins organization and was part of the five-player trade that sent pitcher Johan Santana to the Mets.
For his career, Humber is 0-0 with a 6.07 ERA in 18 career Major League appearances for the Mets (2006-07) and Twins (2008-09). He went 7-9 with a 5.34 ERA in 23 games (22 starts) for Triple-A Rochester in 2009.
Humber was the Mets' first-round selection in the 2004 First-Year Player Draft, taken third overall.
Currently playing winter ball with Leones de Ponce, Humber is 2-3 with a 4.19 ERA in seven games (six starts). He's allowed 34 hits while striking out 29 and walking 12 over 34 1/3 innings.