Ravens' quarterback Lamar Jackson has shown tremendous improvement as a passer two games into the season, and Kansas City Chiefs coach Andy Reid believes part of that is a result of what the team is asking of him.

"It's wide open," Reid said Wednesday in a conference call with local reporters. "The coordinators and the quarterbacks coach, they've opened the gate for him. They're doing a million different things and he's doing it well and looks like he's loving doing it. ... I think he has a full grasp of the offense and there's just a certain comfort when you play in it, like he has, that you get and I think you can see that in his play."

Last season, Jackson made the second road start of his career - and fourth start overall - at Kansas City, a 27-24 overtime loss. Jackson completed 13 of 24 passes for 147 yards and two touchdowns but said he never quite got in-sync with his receivers after taking over as the team's starter late last season.

"I was thrown in Week 11. I didn't really have chemistry with those guys," Jackson said. "They were with (Joe) Flacco the whole time and I was with the other guys. ... We came out with victories, but this year, I had an offseason. (I) got with my guys, worked very hard through the grind, OTAs, we got better, and it's just showing up on Sundays."

The Ravens struggled in pass coverage during Sunday's 23-17 win over the Arizona Cardinals, giving up seven plays of 20 yards or more through the air. Coach John Harbaugh on Monday said that many of those big plays were because of a lack of communication in the secondary, which led to lapses in zone coverage.

Ravens cornerback Marlon Humphrey on Wednesday accepted responsibility for multiple breakdowns in coverage.

"A lot of those were on me this past week," Humphrey said. "I had a couple busts there that he was just so open, it looked like it was the safety's fault, but a few of those were on me. Definitely (going to) clean that up, watch it on film and get it corrected this week because Kansas City is really good, but when you give them the big play, they turn from good to great."

Sunday's matchup with the Chiefs will mark the fifth time Ravens coach John Harbaugh has gone head-to-head with Chiefs coach and mentor Andy Reid.

Harbaugh spent nine seasons working under Reid as a special teams coordinator and secondary coach before being hired as Ravens coach in 2008.

Before last season's meeting between the teams, Harbaugh spoke about the many lessons he still learns from Reid.

Harbaugh is 1-3 against Reid, with his lone victory coming in their first meeting in 2008. He joked about "matching wits" with his mentor but then more sternly answered, "It's been great to play him over the years. We haven't won enough of them."

"(Harbaugh has) done a heck of a job," Reid said. "It's so unique how he and (former general manager Ozzie Newsome) and the whole group there have been able to retool and bring new people in and everybody excels. So you know you're in for a well-coached football team that's going to be physical."