Before 49ers quarterback Colin Kaepernick became a star and, along with several contemporary athletic quarterbacks, changed how his position can help a team's rushing attack, he made his first career start against the Bears on a Monday night in November 2012.
Bears linebacker Lance Briggs had no trouble Wednesday summoning his lasting memory of that 32-7 defeat.
"Touchdown, San Francisco! Touchdown, San Francisco!" Briggs said, mimicking the voice of a public address announcer.
The Bears cannot afford a repeat performance this Sunday night if they are to get their season on course after a Week 1 overtime loss at home to the underdog Bills.
For Briggs and the defense, that means tightening a run defense that — statistically, at least — picked up where it left off in a dreadful 2013.
"A lot of people don't think we can stop the run," Briggs said. "But when we turn the tape on, it's a very different outlook than what everybody else sees. We lost to a team we really shouldn't have. Defensively, we were a couple of plays away from playing the type of defense we really want to play."
Close might count in horseshoes, but it didn't in defending against the Bills.
The Bears surrendered 176 yards and a touchdown on 28 designed runs. Sure, if you disregard the Bills' 47- and 38-yard runs, the Bears allowed an average of only 3.5 yards per carry. But that 38-yarder set up the game-winning field goal. Each yard counted.
And so the Bears are preparing to stop a 49ers power rushing attack that also features Kaepernick and the zone-read option, the same concept that produced the Bills' longest two rushes on Sunday.
"What is the key to that?" safety Ryan Mundy said. "The biggest thing that we learned from the game on Sunday is that we can have 10 guys in the right spot, but if one guy is out of place, there's potential for a big play against us."
Against the Bears, the Bills rushed 20 times out of the shotgun formation with either an inside handoff or a quarterback keeper. It's difficult to determine whether quarterback EJ Manuel truly executed a read option on each of those, but the conflict in which those rushes put the defense basically was the same.
Those 20 rushes gained 152 yards. But take away the two long runs, and the Bears surrendered an average of only 3.7 yards on 18 rushes. That, at least, is why the Bears are confident in their ability to defend the 49ers' zone-read.
"For the most part, we fit well." Briggs said. "But it has to be a complete-game type of thing. It can't be a good game of stopping the run, and then you give up two big runs."
Briggs took responsibility for the 47-yarder at the end of the first half. Instead of defending the gap between the center and one of the guards, he vacated the middle and chased Manuel wide. That left safety Chris Conte alone to tackle Anthony Dixon at full speed. Dixon gained 35 yards after Conte missed.
"My eyes, with my eyes," Briggs said when asked why he botched his assignment. "You know what? I saw the read-option. We were in an eight-man front. I should have just stayed in my gap. That's a mistake that I don't normally make, and I won't moving forward."
Besides eye discipline, stopping the zone-read option requires players to be disciplined and patient in their assignments.
That challenges instinctive defenders who are conditioned to seek and destroy.
"If I have the dive, I take the dive," defensive end Jared Allen said. "The day I get caught peeking in — I don't care if the quarterback runs around me and I'm the only one standing there and it looks like I blew the play — if I have the dive, I have to take the dive.
"For me it's hard. It's hard not to be aggressive, and you have to put the brakes on at times and you have to realize, 'OK, I have this guy. I have to be disciplined here.' Otherwise, I let everyone else down."
Kaepernick and the 49ers figure to test every bit of that.
"You have 10 guys playing the defense correctly and one guy doesn't fit up right, it's a potential for disaster," Mundy said. "So can it get frustrating? Sure. But do we get down on a guy? No. We make the corrections and we rally together and go back to work."