The injury occurred during practice Wednesday. Coach John Harbaugh confirmed Thursday that the fourth-round pick from Virginia was lost for the year.
Harbaugh says, ''It's a clean tear. That's the positive.''
Urban is no stranger to injury. He tore the ACL of his left knee before and had a bad ankle injury during his senior year at Virginia.
This injury occurred when Urban was trying to shake off a block.
Harbaugh says, ''His knee just buckled on him.''
The 6-foot-6, 298-pound Urban signed a four-year, $2.52 million contract in May that includes a signing bonus in excess of $300,000.
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