The Bears remembered the embarrassment of being bullied and shoved around in the ground game by the Raiders in London two years earlier.
They came to the new Raiders home in the desert Sunday and paid them back.
With the running attack powering through the Las Vegas defense and with Khalil Mack gaining a measure of revenge by making two sacks of his friend Derek Carr, the Bears dominated from the first quarter on in a 20-9 win, their first road victory this season.
"Well, it was tough for all of us because you go back to that game, as good as it feels right now after this game today right now, the type of game we played, that feels good," Bears coach Matt Nagy said. 'It didn’t feel like this in London. It felt the opposite.
"And, you know, when you've got to fly the whole way home from London with that feeling in your stomach, you remember that. I don't care what anybody says, you remember that."
The defense held the Raiders to 252 yards and the offense more than doubled the Vegas rushing yardage total of 71 yards, as they ended up with 143 rushing yards.
The ground game was huge in a 16-play, 86-yard drive the Bears used to go up 14-3 in the second quarter, ending with Damien Williams' spinning 4-yard TD run.
Rookie Khalil Herbert gained 75 yards on 18 carries while Williams gained 64 yards on 16 carries. Herbert had a spinning move to get into the end zone for a 4-yard TD and a 14-3 lead in the second quarter
“It's awesome," quarterback Justin Fields said of the running game. "I think it gets our offense going. I think it gets our O-line confidence that we're moving those guys up front.
"So like I said, if we can get the running game going like that every week, it's definitely gonna open the offense up."
They also relied on a defense that added three more sacks, including the two by Mack. Mack actually made another one which didn't count on the stats because it was on a two-point conversion.
"I feel like that's been a Bears thing, that's Chicago Bears," safety Eddie Jackson said. "Defense go out there and play, try to hold them to no points.
"The biggest thing for us was finishing. Coach Sean (Desai) practiced on finishing. We know we was getting outscored in the fourth quarter (this year), so we just wanted to dominate today and play a full four-quarter game. We gave up one touchdown, but overall the defensive play was good."
The Bears hung tough through some cheap shots and intimidating tactics, dealt a few of their own back, knocked Carr out of the game for a few plays, then hit the Raiders with the running game and defense in a physical war that Nagy equated to the Wilder-Fury fight held on Saturday night in Vegas. It was so physical it cost them Fields for a few plays due to a knee injury.
"I knew I hyperextended it," Fields said. "I was just trying to see if I could get up and I was just able to walk off the field and then after a while I could start feeling my strength getting back, so I was just trying to see how stable it was and seeing if I could run on it."
They didn't need much from Fields in the passing game during his first game since officially being anointed starter. Fields hit on 12 of 20 for 111 yards without an interception and threw his first career touchdown pass.
It was a 2-yarder to Jesper Horsted on a rifle throw at the back of the end zone in the second quarter for a 7-3 lead, and they never gave up the advantage.
"Another good ball from Justin," Horsted said. "It was a roll-out to the right and I'm on a corner route there and I just kind of made eye contact with him as he was scrambling and slowed it down a little bit because the defender has his back to me and Justin just trusted me enough to put the ball up and I made the catch."
Fields' biggest completion might have been a third-and-12 deep in Bears territory after the Raiders had closed within 14-9 on Josh Jacobs' TD dive in the fourth quarter. Momentum seemed to be shifting.
Fields shot a low pass in over the middle through eight-man zone coverage to Darnell Mooney to keep a drive going for a 46-yard field goal by Cairo Santos for a 17-9 lead.
"You know, they had a great drive," Williams said. "They went down, they had the momentum. What we did was, we quieted that."
A three-and-out later Santos added another 46-yarder, his 34th straight field goal without a miss for the clinching points and a huge crowd of Chicago fans went home happy, or at least to the casinos happy.
"We talk about how well we travel, and it's amazing all over the country when we go to certain spots," Nagy said. "But today it felt, you could really, I mean it was impactful. And so I think it's a beautiful win for everybody."
Much better than a trip home from London two years ago.