The team did not give details of the injury or a timetable for Murray to return.
The top rusher in the league last season canceled plans to speak with reporters.
Backup running back Ryan Mathews, who would take over if Murray was out, said after practice that he didn't think the injury was serious and that Murray would be back at practice on Thursday.
Murray has been held to 11 yards on 21 carries in his first two games with the Eagles. He signed as a free agent this offseason.