The Nationals sent third baseman Ryan Zimmerman's MRI results to team doctor Wiemi Douoguih and will learn more about the nature and severity of his shoulder injury Wednesday, but Zimmerman will rest for at least another few games and a stint on the disabled list appears possible, if not likely. "At this point, as far as I know, it's not real favorable," Manager Davey Johnson said. "It looks like he's going to need to some more rest. We'll just have to wait and see." The Nationals planned to wait at least until Wednesday to make any roster moves. If Zimmerman lands on the disabled list, Johnson said he would use Mark DeRosa, Chad Tracy and Steve Lombardozzi to replace Zimmerman at third base.