"Moss is that receiver that will go get that ball and make you look good," Bears defensive end Adewale Ogunleye said. "Culpepper still runs very fast; he's still elusive. He's a big, strong quarterback. But without Moss there, defenses are playing him straight up."
The Vikings leading wideout is free agent acquisition Travis Taylor. He has 18 catches for 215 yards and two touchdowns. Rookie Troy Williamson is their speed threat with nine grabs for 166 yards and two scores. Former Bear Marcus Robinson is averaging 19.9 on eight receptions, but has yet to find the end zone.
In fact, much of the struggles have come inside the red zone, an area where Moss' size would often mean a touchdown when the Vikings moved inside the 20. Through four games, Minnesota has a 27.3 percent (3-of-11) touchdown conversion rate to rank 30th in the league. Conversely, the Bears lead the NFL in red-zone defense for touchdowns allowed at 11.1 percent (1-of-11).
"It's not the same when you're preparing for them," said safety Mike Brown. "You spend a lot of time on Randy Moss because he's the only player now in the league where you have to change your defense for one guy. It used to be him and Marshall Faulk; now it's just him."
The loss of Pro Bowl center Matt Birk has impacted the entire offensive line. The unit has surrendered 20 sacks, which is tied for the second highest total in the NFL.
The running game has also been limited because Moss forced teams to play off the line of scrimmage in order in an attempt not to let him beat them deep. As a result their average of 4.7 yards per carry last year is now down to 3.8. The difference is trying to block more men in the box.
"The Vikings haven't had to face that because of the Randy Moss factor," said MLB Brian Urlacher. "He's been out there and teams have had to double -team him every play and that's not the case anymore. So it is a little different trying to run the ball when you have got eight guys in the box."
The Bears defense has been solid against the run this year, ranking fourth in the league. Chicago has been burned by the Vikings running backs because of the respect they had for Moss. Onterrio Smith rushed for 94 yards and caught six balls for 104 yards in Week 3 of 2004.
Another loss in the off-season for the Vikings was the departure of offensive coordinator Scott Linehan, who is now calling plays for the Miami Dolphins.
"Coach Linehan is a great coach, and anybody he leaves from is going to miss him — anybody," Culpepper said. "But he's not here now. The thing we have to worry about is what we've got, and we've got to deal with it and go out and get the job done."
Considering the Bears have given up a number of big plays in consecutive loses, the Vikings could be just what the defense needs to get back on track.