Urlacher needs to get to grips with Manning's array of plays
Super Bowl XLI
Indianapolis v Chicago
Dolphins Stadium, Miami
Sunday, 4 Feb, 2325 GMT
Sunday's Super Bowl in Miami is being billed as a battle between two teams with differing strengths.
The potent offence of Indianapolis is tipped to overcome the defensive powers of Chicago at Dolphins Stadium.
Pulling the strings for the Colts is quarterback Peyton Manning, while Bears middle linebacker Brian Urlacher is one of the NFL's best defensive players.
Chicago QB Rex Grossman is inconsistent but could make it a close contest if he is at his best.
Manning, 30, is a future Hall of Famer - the only player in NFL history with 3,000 passing yards in each of his first nine seasons.
But he has long had a reputation for failing to deliver his best performances in games where it really matters.
However, Manning is getting smarter with age, and his ability to force the pace against tiring opponents helped the Colts clinch the American Football Conference after three years of faltering in the play-offs.
Manning is on the verge of confirming his all-time great status
He will be looking for wide receivers Marvin Harrison and Reggie Wayne to make an early impact and sow doubts among the underdog Bears.
Chicago won the National Football Conference behind a defence that allowed an average of just 15.9 points per game.
Cornerbacks Charles Tillman and Nathan Vasher have had fine seasons but may struggle if the Colts are quick off the mark.
Tailback Joseph Addai, outstanding in his first NFL campaign, also has the pace to cause the Bears plenty of problems.
Chicago coach Lovie Smith has loyally backed Grossman, but a number of error-prone displays this season have shown he cannot be relied upon.
The Colts are not the greatest in defence, however, ranked 21st out of 32 teams in the regular season, and have weaknesses to exploit.
They are susceptible on kick-off returns, for example, and Bears' specialist Devin Hester has run the ball 528 yards back the way it came in his rookie campaign.
Chicago also have in Robbie Gould the NFL's top-rated kicker in the regular season.
Indianapolis, however, have a decent kicker of their own - Adam Vinatieri, who won three Super Bowls with New England, two on nerveless last-gasp efforts from his boot.
The Super Bowl is more likely to be decided, though, on Manning's ability to outfox Urlacher and his defensive cohorts.
Live updates on Super Bowl XLI on this website from 2315 GMT on Sunday, 4 February, plus live commentary on BBC Radio Five Live.