LAKE FOREST, Ill. -- Nobody had a closer relationship to Matt Nagy in Kansas City than longtime NFL coach Brad Childress, who announced his retirement following the Chiefs’ playoff loss to Tennessee last weekend.

Childress, the former head coach of the Minnesota Vikings from 2006 to 2010, had worked alongside Nagy in Kansas City since 2013. Childress held a variety of titles under Chiefs head coach Andy Reid, including that of co-offensive coordinator with Nagy for the 2016 season.

"Brad Childress, my partner, we spent five years together,” Nagy said Tuesday during his introductory news conference as Bears head coach. “My partner in crime. Every day he was telling stories and being there for me, being there with me. He has a special place in my heart and I just thank him from the bottom of my heart.”

Childress is an authority on Nagy, who at just 39 years old is an unproven commodity as a first-time NFL head coach. During an appearance on ESPN Radio 1000 in Chicago on Wednesday, Childress expressed confidence that Nagy will change the Bears' style on offense, which had grown way too conservative in recent years.

During the combined three seasons of the much-maligned John Fox era (2015-17), the Bears' offense tied for 30th in the league in points per game (18.29) and Total QBR (41.6), and 25th in yards per game (329.5), according to ESPN Stats & Information.

“I think you’re going to see some different things offensively,” Childress said. “I think his record is proven that he’ll do some things differently offensively, and let’s face it, you have to score points to win. I think we [Kansas City] finished fifth in points scored last year.

“I know for a fact, because I sat in on the Mitchell Trubisky interviews before the draft with Matt and Coach Reid -- we had him for seven hours -- I know that Matt still has his notes from that interview. He’s very excited about him [Trubisky]. I thought he was a bright-eyed guy. We put him in a tough environment when teaching him plays and making him regurgitate details and specifics. I couldn’t have been more impressed with that guy. But with that said, you got to put guys around that guy. A quarterback can’t do it himself. People always have to play around a quarterback for a quarterback to play well.”

Nagy acknowledged on Wednesday that he -- not Reid -- was solely responsible for the questionable playcalls in the second half of Kansas City’s wild-card loss to the Titans.

Still, Childress points to Nagy’s overall body of work as a playcaller, which included the final four games of the 2017 regular season when Kansas City went 4-0, as proof that Chicago hired the right offensive mind.

“I thought he was excellent as a playcaller,” Childress said. “I thought he was able to put together the openers -- the first 15 plays each game -- and keep teams off balance. He’s not conservative. He’s a guy that understands that you have to be able to throw the football in the National Football League, but still has a great appreciation for the run. You got to be able to run it when everyone knows you are going to run it."