"You've got to understand the situation, facing a division opponent, knowing we're going to face them twice a year," Mack said. "We've got to make that jump, and you saw it today."
Mack made a sack, a forced fumble in the red zone and a recovery, Adrian Amos intercepted Cousins to thwart another possible scoring attempt and Jackson made the play of the night with an interception and 27-yard touchdown return with the Vikings (5-4-1) down 14-6.
"They were trying to make some big plays and the [interception] was one of their big plays, so I read the quarterback's eyes," Jackson said.
A week after hitting the uprights four times, Bears kicker Cody Parkey made three field goals, including the clinching 48-yarder with 2:48 left to give the Bears (7-3) a 1 1/2-game lead in the NFC North.
Teammates flooded around Parkey after he hit it. Earlier he'd made kicks from 33 and 41 yards.
"That was pretty cool," Parkey said. "Obviously they saw me down last week and they picked me up. That's what's special about this team and that shows how close we are."
The Bears wanted to make a statement about being a contender.
They continued to get out to strong starts on offense, outgaining the Vikings 202-77 in the first half when they spread out the attack. They had 15 first downs to the Vikings' five and converted 3-of-5 third downs against the NFL's best third-down defense in taking a 14-0 lead.
Trubisky finished 20-of-31 for 165 yards with two interceptions and an 18-yard touchdown pass to Anthony Miller. His 43 rushing yards loomed big, too, as the Bears moved their quarterback repeatedly.
"You've got to do that against a great pass rush team, which they have," Trubisky said. "They kind of tired out running side to side, a little misdirection."
The Bears converted 6-of-12 on third downs, a high percentage against a defense allowing 25.7 percent conversions on third down.
"They are ridiculous on third downs," Trubisky said. "That's impressive on our part, just trying to stay on the field and focus on third downs and move the chains."
Miller made an 18-yard diving catch from a Trubisky rollout toss for a 10-0 lead in the second quarter. And Parkey converted first-half field goals of 33 and 41 yards. The Bears aggressively went for two after Miller's score and Trubisky found Josh Bellamy for the conversion.
But it was a night that belonged to Chicago's defense.
"Our defense is spectacular," Trubisky said. "They brought it again this week, and they just continue to amaze the offense."
Cousins completed 30-of-46 passes for 262 yards eventually, but in the first half threw a wobbly duck of an interception downfield to Amos under heat from pass rusher Leonard Floyd. The Bears also took the ball back in the first quarter when Mack stripped it from running back Dalvin Cook and fell on it at the Bears' 15-yard line.
Then came the fateful interception and touchdown return by Jackson with 8:30 left in the game.
"We talked about in the red zone and getting down in that scoring zone and we needed to come away with touchdowns, not field goals," Cousins said. "And unfortunately, especially in the first three quarters of the game, we kept coming away with field goals or even worse - turnovers.
"And that certainly put us behind the 8-ball."
A pair of Bears turnovers led to two 36-yard Dan Bailey field goals and cut the deficit to 14-6 early in the fourth quarter. Anthony Harris picked off a Trubisky pass and returned it 33 yards to the Bears' 36, and Cohen lost a fumble that was recovered by Harrison Smith at the Bears' 18-yard line.
But the Vikings couldn't get into the end zone until Cousins found Aldrick Robinson for a 13-yard touchdown with 4:51 left, and a two-point conversion pass to Adam Thielen cut the deficit to 22-14.
"We made enough mistakes tonight that didn't allow us to win," Vikings head coach Mike Zimmer said. "Most of it was missed tackles in the first half."
The Bears' Benny Cunningham fell on an onside kick after Stefon Diggs had scored on a 5-yard touchdown pass with 48 seconds left in the game. It left the Bears heading to Detroit for a Thursday game on a short turnaround.
Both tight end Adam Shaheen and outside linebacker Aaron Lynch left the game with concussions for the Bears.