Wheeler, 21, had been scheduled to pitch on Friday. The former first-round draftee was diagnosed with an avulsion -- defined by dictionary.com as "a tearing away" -- to the nail on his right middle finger. Wheeler is 1-2 with a 1.75 ERA through his first five starts with Binghamton.
The Mets acquired Wheeler, the sixth overall selection in the 2009 First-Year Player Draft, last summer in a July deal with San Francisco. The Giants received Carlos Beltran in the trade.
Wheeler is 13-12 with a 3.43 ERA and 229 strikeouts in 199 1/3 innings as a professional. The Mets are expected to start right-hander Gonzalez Germen in Wheeler's place on Friday. German, 24, has gone 3-0 with a 3.04 ERA in five appearances -- four starts -- for Class A Port St. Lucie.
Spencer Fordin is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.