Martinez was examined Friday night for a strained oblique, but no decision was reached. He will be reevaluated Saturday.
Outfielder J.D. Martinez was recalled from Triple-A Oklahoma City to take Fernando Martinez's spot on the roster.
Fernando Martinez, 24, played in 41 games for the Astros last year, hitting .237 with six homers and 14 RBIs. Houston acquired him in January 2012 off waivers from the Mets.
J.D. Martinez, 25, appeared in 53 games for the Astros in '11 and in 113 games last year. He hit .241 last year with 11 homers and 55 RBIs.
Gene Duffey is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.