Khalil Mack thought he knew what celebrity star status was in the NFL. He had good reason to think so. He was a three-time Pro Bowler and former Defensive Player of the Year for the Oakland Raiders. One of the storied franchises in pro football history. He’s widely revered as one of the best pass rushers in football. Everybody knew his name, right?

Sure, but not to level he thought. The thing about Oakland is it’s not a major media market or a major sports city. If it were the Raiders wouldn’t have moved once before and wouldn’t be moving again. The Bears are a charter franchise in football history and Chicago is the third-largest media market in the country. Its fans are crazy about their sports, none more so than this team.

Mack admitted this week that he had no idea what he was signing up for when the Bears traded for him. Since the start of the season, he’s been the best defensive player in football with five sacks, four forced fumbles, and an interception. Chicago is 3-1 and leading the NFC North for the first time in 2013.

He’s the first genuine star the Bears have had on defense since Brian Urlacher, and the fans have apparently been quick to remember his face.

Khalil Mack has been having random, weird encounters off the field

Mack has met fans in the past, but he admitted during a meeting with the press that he wasn’t prepared for how different people from Chicago are. It’s an entirely different level based on what he’s experienced thus far.

“I didn’t know Chicago was so aggressive,” Mack said. “It’s real aggressive out here. Everybody kind of recognizes you out here. But it’s a good feeling…

That’s the difference [from Oakland] — it’s everywhere,” he said. “It don’t matter where I’m at — HomeGoods. It could be a mother of two. And she’ll be a fan. And it’s random as hell to me.”

The truth of the matter is Oakland, while a great sports town in their own right, has never been overly kind to defensive players. When one thinks about the Raiders they think about Ken Stabler, Jim Plunkett, Marcus Allen, Tim Brown, Fred Biletnikoff and other great offensive players. Not many defensive names have gotten the limelight in the past.

That is the complete opposite in Chicago. No city embraces the defensive culture in football more, especially at the linebacker position. The Bears have had 12 Hall of Famers who played exclusively at one position in their careers. Eight of them came from the defensive side of the football. That should help explain what Mack has gotten himself into.