Hatcher said Wednesday he will have an arthroscopic procedure to clean up some cartilage.
The injury comes as the Redskins are wrapping up their offseason practices. If the timetable holds, he would be able to practice around the start of training camp on July 23.
Hatcher wore a compression wrap around his left leg as he watched Wednesday's minicamp session.
Hatcher signed a four-year, $27.5 million contract with the Redskins in March as a free agent from the Dallas Cowboys.
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