Humber, 23, had been pitching with Class-A St. Lucie of the Florida State League, where he was 3-1 with a 2.37 ERA in seven starts.
The Mets' first-round selection in the June 2004 draft, Humber had won two of his last three decisions. In 38 total innings, the Rice University product struck out 36 and walked nine while limiting opponents to a .178 average.
Humber, a power pitcher from Carthage, Texas, made one appearance with Binghamton last year after beginning his professional career at St. Lucie. Humber pitched four innings at Norwich on July 11 before leaving with discomfort in his pitching elbow; he underwent season-ending 'Tommy John' surgery eight days later.
Binghamton also called up right-hander Joe Smith, the Mets' third-round selection in the June 2006 draft, from Class-A Brooklyn of the New York-Penn League.
Smith, 22, was 0-1 with a 0.45 ERA and nine saves in 17 appearances for Brooklyn. In 20 innings, Smith had allowed 10 hits, striking out 28 and walking three, limiting opponents to a .141 average.
In other roster moves, the B-Mets announced they have placed right-hander Miguel Perez – the reigning Eastern League Pitcher of the Week – on the temporary inactive list.
Right-hander Tim McNab and outfielder Rashad Eldridge were activated from Binghamton's disabled list and sent to St. Lucie and Triple-A Norfolk, respectively. Right-hander Robert Paulk was also sent to St. Lucie.