Dodgers catcher Russell Martin is expected to be sidelined for four to six weeks after an MRI revealed a pulled groin.

Martin likely will miss Los Angeles' regular-season opener on April 5 at Pittsburgh.

A.J. Ellis , who has just 13 career major league at-bats, will get the bulk of the catching duties with Martin out. The Dodgers also have veteran backup Brad Ausmus , who turns 41 in April.

Martin first felt discomfort during a running drill a few days before the Dodgers ' first spring game Friday. He started Friday's game against the White Sox and played five innings, even stealing a base.