With Ryan Church hampered by a hamstring injury, the Mets could call up top outfielder prospect Fernando Martinez. Church could end up on the disabled list with the injury, which would force New York to make a roster move. The Mets don't want to promote Martinez without regular playing time available, but with a host of injuries, there is a regular spot open. Martinez, 20, is hitting .294 with seven homers and 26 RBI at Triple-A Buffalo. "That would definitely be the guy," a team source said.