This news comes three weeks after Richardson sat out offseason practices due to a hamstring injury brought on by conditioning issues.
"When he gets himself (in shape), he's got talent," coach John Harbaugh said at the time. "I'm very certain he'll get there. And when he does, we'll be able to evaluate him."
Needless to say, the knee procedure on top of the time lost to conditioning woes will shorten Harbaugh's window of evaluation. It also decreases Richardson's already long odds of making the Ravens' final roster in September.