Coach John Harbaugh says Monroe was scheduled to undergo ''a minor surgical'' procedure and will miss ''a number of weeks.''
Monroe has been a key figure on an offensive line that far has enabled the Ravens to average 4.6 yards per rush. In addition, quarterback Joe Flacco has been sacked only three times in three games.
Hurst was a four-year starter for North Carolina before signing as a rookie free agent in May. He has played in all three games as a backup for Baltimore.
Flacco says, ''It's definitely going to be different for us an offense.''
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