When the Browns and Vikings face off at Twickenham Stadium in London on Sunday, a pair of good friends will be pitted against each other for a few hours.

Vikings Head Coach Mike Zimmer and Browns Head Coach Hue Jackson spent time as the Falcons defensive and offensive coordinator, respectively, in 2007 and again worked together at Cincinnati from 2012-13.

"Mike's a very special coach, a very special person in my life. He taught me defensive football," Jackson told Twin Cities media members via conference call earlier this week. "He's as fine a coach as there is in the National Football League."

Jackson appreciates Zimmer's "brutal honesty" and directness in relaying his expectations but also motivating those around him.

"And then I think he has a tremendous vision of how he wants his defensive football team and his team to play, and he's able to have that manifest itself through his coaches and through his players," Jackson said. "I really enjoy talking football with Mike because he's a football man through and through, and there's no B.S. that way. He is always working at trying to get better and trying to be better for his football team and for his organization."

Jackson said he knows he will have his hands full facing a powerful Minnesota defense that's been built over the past three-plus seasons under Zimmer.

A Zimmer-coached football team has two staples, according to Jackson: Its defense is difficult to score against, and they'll find a way to get to the quarterback.

"Those are the two things that I know are going to happen," Jackson said. "And I think we know how good the team is defensively on third down. That's who Mike Zimmer is.

Added Jackson: "His job, he truly believes, is to get the other team off the field as fast as he can, whether it be on third down or whether it be by turnover."

Here are a few other highlights from Jackson and Browns quarterback DeShone Kizer's media sessions:

Jackson on Vikings defending the run

"I think they play together. I think they're playing with a lot of unity as a group. They have really good players, first of all. [Everson] Griffen, you just name anybody within that front seven, I think they're all playing extremely well. A very talented secondary – I spent time with Trae Waynes myself. I mean, there's a guy who's 39 years old and is playing as well as he played, sometimes, in his middle years. There's a lot of talent, but I think more so than anything, they know what Mike wants and what Mike expects, and so that's what they play to, and that's what they give him."

Kizer on Vikings defense

"They're very good all the way across, and they have a very good defensive coordinator. Obviously Coach [Jackson] has been able to go up against a very similar-style defense with the Cincinnati connection, and we have to make sure we do whatever we can to correct some of the things that we've done in the past.

"First of all, it's making sure that we understand where our weaknesses have been in the past, attack those, make sure that we can firm up there, and then go back and watch them [on tape] and make sure that we can combat against some of their pressures they have with some very good blitzers in the secondary, but also at their linebacker corps."

Jackson on facing Everson Griffen without LT Joe Thomas

"You start praying and see if you can get seven guys over there at one time to block him. He's a tremendous football player, extremely explosive, strong, looks like he truly understands the game. So that's a tall challenge for us, and we get it. But we're excited about facing him. I mean, how else do you measure yourself? You have to measure yourself against some of the best players in the league, and he's one of them."