Nationals second baseman Daniel Murphy has been using crutches to get around the team's annual fan festival about eight weeks after having right knee surgery.
Murphy says he doesn't want to offer any timetables about his recovery or when he might be ready to play.
New Nationals manager Dave Martinez says Murphy told him he expects to be ready for opening day.
Murphy says he felt something was wrong with his knee for the last three games of Washington's NL Division Series loss to the Chicago Cubs.
He is not sure whether the injury was a result of a particular episode or overuse or a combination of the two.