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Heading into Monday night, Derek Carr was a frontrunner in the MVP conversation and the Las Vegas Raiders were flying high with a 3-0 start to the season, but Justin Herbert and the Los Angeles Chargers were hot off of a win over Patrick Mahomes and the Kansas City Chiefs at Arrowhead Stadium, and looking to send another message to the AFC and league as a whole. They'd achieve that mission by handing the Raiders a 28-14 defeat in primetime, one that wasn't without controversy that began with a strange lightning delay (SoFi Stadium is an indoor facility) and ended with head coach Jon Gruden criticizing the design flaws in the arena.

A key reason for the Chargers victory wasn't simply how great Herbert looked, and he did look great, but so did All-Pro pass rusher Joey Bosa and the Los Angeles defense for much of the evening. They held Carr and the Raiders offense to no yards and no touchdowns in the first quarter and only 51 total yards at the half, still with no touchdowns.

"We knew once we hit him a few times, he really gets shook," Bosa said, via Daniel Popper of The Athletic. "And you saw on [defensive end Christian Covington's] sack. He was pretty much curling into a ball before we even got back there. Great dude, great player. 

"... But we know once you get pressure on him, he kind of shuts down."

On the whole, Carr was sacked a total of four times and passed for just 196 yards and one interception to go with his two third quarter touchdowns. The Chargers pressure came from all over, with four different players landing a sack, namely Bosa, Covington, Kyler Fackrell and Jerry Tillery. Carr was also hit seven times through four quarters, as the Chargers did their best to shorten his internal clock and keep him wildly uncomfortable -- forcing a variety of overthrows that included downfield strikes that could've changed the outcome of the game in a major way.

Bosa's comments aren't entirely correct, though. After all, Carr was sacked a total of eight times heading into Week 4 and was still able to play hero on more than one occasion en route to the 3-0 start, and he was averaging 401 passing yards per game (highest in the NFL through the first three weeks) with a 101.4 passer rating and six touchdowns to only two interceptions. But, to Bosa's point, Carr couldn't get in gear for three of the four quarters against the Chargers defense, and now Los Angeles has officially served notice they're challenging for the AFC West title in 2021, and possibly more.

The Raiders and Chargers meet again in the regular season finale, but this time it'll be held at Allegiant Stadium, and you can bet Carr will have Bosa's quotes taped to his locker for what could be a division-deciding clash at best or, depending on how things shake out elsewhere in the AFC, a win-and-get-in scenario.