The back-and-forth has already started between the Los Angeles Chargers and Kansas City Chiefs, long before the two teams are scheduled to face off on the field during the upcoming season.

The talk started Tuesday, somewhat, when Chargers wide receiver Keenan Allen was asked during a media session about the additions the Chiefs have made to their defense over the offseason. Allen avoided saying anything about any players in particular, but his response and body language to the question made it seem like he didn't have much respect for what he'll be facing against the Chiefs.

"Thoughts on it? Nope," Allen said. "But since you asked, it was brought up today in the locker room. We just looked at their DB group and uh... (shaking head) I'll just leave it at that. We've seen it, yeah."

Chiefs safety Tyrann Mathieu addressed Allen's comments during an interview with Alex Gold on the SBNation Radio podcast Wednesday. Mathieu made it clear he'll be keeping Allen's comments in mind when the Chiefs and Chargers play this season.

“I think the last three years, the Chiefs have pretty much won the AFC West,” Mathieu said, per ArrowheadPride.com. “I think a lot of receivers feel that way. I think we should really get these guys a reality show, let them just talk about their feelings and emotions, they’re pretty much all over the place. He’ll have his chance to go against us and to play against us and quite honestly, we won’t forget the things he’s done, so it’s kind of easy for receivers to talk a lot of smack. They get 160 targets a year, so it’s easy to catch 90 balls. He’s a pretty good player, he does well for his offense, but yeah. I’ll just leave it at that.”

The Chargers notched their first win over the Chiefs since 2013 the last time the two teams played, which was a 29-28 comeback win at Arrowhead Stadium in Week 15 of the 2018 season. The Chiefs defensive backs were given some criticism over their role in letting the Chargers rally in that game, with Allen even reportedly referring to cornerbacks Kendall Fuller and Orlando Scandrick as "Doo-doo" and "Doo-doo 2." Allen and the Chargers will be facing a Chiefs defense with a number of new faces this season, including Mathieu, cornerback Bashaud Breeland, safety Juan Thornhill, and defensive linemen Frank Clark, Alex Okafor, and Emmanuel Ogbah. The Chiefs and Chargers will face off on November 18 in a Week 11 Monday night game in Mexico City, then will meet for the second time in a Week 17 game at Arrowhead Stadium. Both games could have a significant impact on who wins the AFC West, which is a goal Allen said his team has their eye on as they head towards the 2019 season.

"No doubt," Allen said. "It's on our mind. We know how important it was last year."