Chicago Bears fans were shocked when they learned in September that the team traded for all-world pass rusher Khalil Mack. It was a franchise-changing move that directly led to a 12-4 record and NFC North crown in 2018.

It didn’t take long to see how dominant Mack would be for the Bears. His Week 1 debut against the Packers, in which he forced two turnovers and sacked Aaron Rodgers twice, grabbed headlines.

It also grabbed the attention of his former Raiders teammates.

“Our first game was on Monday night against the Rams. [The Bears’] first game was on Sunday night against Green Bay. So we were able to sit down and watch their game before we went to our hotel room,” Cowboys wide receiver Amari Cooper said on “The ThomaHawk Show” podcast during Super Bowl week. “And obviously, everybody knows how he dominated that game. He had like a pick-6, a sack-fumble, another sack. He just wreaked havoc that whole game.

“And guys were kind of looking at the game like, happy for Mack, but mad for the organization. We actually had to have a meeting about what Mack did on that Sunday night. So we played Monday, we came back in Wednesday, we had a meeting about that. Because some guys were just mad, like, ‘Are they really trying to win here? Or am I just here for nothing?’ ”

Little did Cooper know at the time that he’d be the next big-name Raider to be traded away by Jon Gruden. Cooper was dealt to the Cowboys in October for a first-round pick.

The Mack trade is one that will continue to have a massive impact in Chicago — and an equally massive impact, for all the wrong reasons, on the Raiders.

Related Super Bowl LIII shows importance of Bryce Callahan to Bears defense

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