Linebacker Brian Urlacher wasn't the only missing Chicago Bear when the preseason began
Thursday with a 31-3 loss to the Denver Broncos at Soldier Field.

The Bears matched their worst preseason loss under coach Lovie Smith -- they lost by 28 to the Giants last year -- without running back Matt Forte, defensive end Julius Peppers and quarterback Jay Cutler stepping on the field.

Cutler being withheld had more to do with the birth of his son on Wednesday. He went through warmups in a lightning storm-shortened pregame, then Smith decided not to play him.

"Of course, he had a lot of things going on this week," Smith said.

Jason Campbell started and went 4-of-5 for 13 yards.

"I knew there might be a chance I might play, not  knowing for sure what day Jay's baby would come out," Campbell said. "We found out it happened Wednesday morning. And, of course, he still wanted to play, but we felt as a group ... coach made a decision. That was probably best because this is an exciting time in his life, and he really needed to take the time to enjoy it."

Peppers and Forte had been nicked up a little in camp with minor injuries, and Urlacher had missed six practices -- four due to injuries and the last two for personal reasons. Smith said Urlacher would "be back," but did not give a timetable for his return.

Meantime, the Bears struggled to establish anything offensively with Campbell, Josh McCown, and undrafted rookie free agent Matt Blanchard, who finished up.

"We're not trying to do anything to really show our hand or show what we have right now,"
Campbell said.

They certainly achieved that. The Bears managed just 41 first-half offensive yards and only 6 rushing. Running back Michael Bush, replacing Forte, fumbled a pitchout to set up the Broncos' first score on a field goal.

Tangled Webb: It was probably good that Cutler did not start because the offensive line struggled to block for runs or for the pass. The lineman under the most scrutiny, LT J'Marcus Webb, allowed a sack by backup defensive lineman Robert Ayers, got called for a false start and was kept on the field into the third quarter after all the starting offensive linemen had
left. "If (line) coach (Tim) Holt or coach Tice needs me in there that long then I'm all for it," Webb said.

Major injury: Major Wright has been plagued in two-plus seasons by numerous minor injuries that seem to strike him just as he's making strides. It happened again. Wright started out the game by intercepting Peyton Manning's deflected pass near the goal line but left after that because he suffered a pulled hamstring. "I just felt a little tight," he said. "It wasn't nothing major." No pun intended.

Mac attack: Defensive end Shea McClellin had an eventful first preseason game, producing a sack and hurrying Broncos QB Caleb Hanie into an interception in the second quarter. McClellin also got flagged for a blow to Hanie's head, but it happened by accident. He was running in to help Nate Collins on a sack and Collins spun Hanie around right into McClellin's helmet. "Any time it's your first play and you get a sack as a defensive lineman you'll remember that," Smith said.

Baptism by fire: In their debuts, Bears rookies had mixed results. Wide receiver Alshon
Jeffery made four short catches for 35 yards. ... CB Isaiah Frey showed no awareness of the
ball when covering on a punt inside the 10 that eluded him for a touchback. ... Safety Brandon Hardin was late to move up in zone and break up a fourth-quarter TD pass, and whiffed when trying to make a tackle on a first-half running play along the sidelines.

Baby steps: In his Bears debut, WR Brandon Marshall made one catch for 4 yards and was
immediately tackled. “Well the good thing is I got that one catch out of the way so now I want to catch it and run with it next time," he said.

Follow Bears reporter Gene Chamberlain on Twitter @CBSSportsNFLCHI.