In Urlacher's eyes, those factors don't minimize the task at hand.
"And it doesn't matter who the quarterback is. Luck may be different because he's a rookie, it's his first game, and he may be a little bit excited. But he's a good quarterback. ... We just have to do what we do, no matter the opponent.''
Defensively, the keys to the Bears' success under Lovie Smith haven't been a secret: consistent pressure and creating turnovers. Since 2004, the Bears defense leads the league in takeaways (266), three-and-outs forced (437), three-and-out percentage (26.6 percent) and third-down percentage (34 percent).
"If we get pressure and we can play our Cover-2 behind it, then we're going to be successful,'' Urlacher said. "Anytime you can drop seven guys — have seven eyes on the quarterback — and have pressure from four up front, that's a good thing for your defense.
"Our guys have done a good job the last few years getting pressure on the quarterback, so I don't think it's going to be an issue this year, either.''
The pressure could improve, though. Last season, the Bears finished with 33 sacks and were 29th in the league in sacks per pass play. Julius Peppers led the team with 11 sacks but didn't get enough help, considering the double teams he often encountered.
The Bears hope first-round pick Shea McClellin makes an immediate impact, at least as a situational pass rusher. There are high expectations for Henry Melton and Stephen Paea as interior rushers too. Melton was second on the team with seven sacks in 2011, including two in a dominating, season-opening performance against the Falcons. He also had six quarterback pressures versus the Falcons.
Can Melton duplicate that effort Sunday?
"I'm not going to go out there and try to do too much,'' Melton said. "I'm just going to go out there and try to play my game."
The Bears should know not to overlook Luck. In Week 4 last season, the Bears faced Panthers rookie quarterback Cam Newton. Newton completed 27 of 46 passes for 374 yards and a touchdown and also ran for two scores in the Bears' 34-29 win.
"Last year against Cam Newton, we were just chasing him all over the field,'' Melton said. "Luck isn't that type of guy. He's no Cam Newton. He's not an outside-the-pocket kind of guy. We just have to get after him with force.''
Defensive coordinator Rod Marinelli mentioned the possibility of blitzing more. The Bears showed a glimpse of it during an exhibition game against the Redskins, when blitzing strong safety Major Wright flushed Robert Griffin III out of the pocket, leading to a forced fumble by Israel Idonije and recovery by Peppers.
"I like to blitz,'' Urlacher said. "All of us linebackers like to blitz. ... Anytime you get a chance to get a sack or get a sack-fumble, it's good.''
Those chances might present themselves Sunday. The Colts could be much improved thanks to Luck's maturity, but the offensive line remains a work in progress.
New Colts offensive coordinator Bruce Arians' spread-the-field attack is likely to feature some no-huddle and rollouts to put Luck in the best position to succeed.
Regardless of how the Colts plan to attack — either with a heavy dose of Luck passing or with more balance, featuring running back Donald Brown — Urlacher believes the defense will be well prepared.
"We just have to play our defense, play fast,'' Urlacher said. "Basically, we just have to do what we do.''