This image released by NBC shows host Matt Lauer, left, posing with Adam Greenberg after an appearance on the "Today" show, Thursday, Sept. 27, 2012 in New York. The Marlins said Thursday that they have signed Greenberg to a one-day contract, effective Oct. 2, and will play him that day against the New York Mets. Greenberg made his big-league debut for the Chicago Cubs on July 9, 2005 against the Marlins, getting one plate appearance but no official at-bat after a 92 mph fastball that struck him in the head. Greenberg was the subject of a campaign called "One At Bat," which lobbied teams to give him a second chance.  The Marlins publicly extended the invitation to Greenberg on NBC's "Today" show Thursday morning.  (AP Photo/NBC NewsWire, Peter Kramer)

Photo by: Peter Kramer

This image released by NBC shows host Matt Lauer, left, posing with Adam Greenberg after an appearance on the "Today" show, Thursday, Sept. 27, 2012 in New York. The Marlins said Thursday that they have signed Greenberg to a one-day contract, effective Oct. 2, and will play him that day against the New York Mets. Greenberg made his big-league debut for the Chicago Cubs on July 9, 2005 against the Marlins, getting one plate appearance but no official at-bat after a 92 mph fastball that struck him in the head. Greenberg was the subject of a campaign called "One At Bat," which lobbied teams to give him a second chance. The Marlins publicly extended the invitation to Greenberg on NBC's "Today" show Thursday morning. (AP Photo/NBC NewsWire, Peter Kramer)