The Kansas City Chiefs (11-3) dropped their first divisional game at Arrowhead Stadium since Week 2 of the 2015 season with a tough 29-28 loss to the Los Angeles Chargers (11-3) on Thursday night.

It was also the Chiefs' first loss at home this season.

They have now lost three games this season by a total of seven points, but with the chance at a division title and all the storylines heading into Thursday—from Tony Gonzalez's induction into the Chiefs' Ring of Honor, the guys wearing the ever-popular red-on-red uniforms, the season debut of Eric Berry, plus the game being in prime time, there was a lot going on.

The Chargers ultimately overcame a 14-point deficit in the games' final five minutes to beat the Chiefs on a successful two-point conversion with just four seconds left in regulation. The Chiefs had led for all but six minutes on the night.

Here are 10 observations from the game:

1. The atmosphere was electric

Despite how the game finished, the Arrowhead crowd was electric on Thursday night, and they were given plenty to cheer for early in the game.

The Chiefs raced out to a fast 14-0 lead after an early takeaway by the Chiefs' defense, which was followed-up by another quick stop on the Chargers' second offensive drive.

The crowd, which is always energized by defense, saw the Chiefs finish with five sacks and 12 quarterback hits on the day. It just wasn't enough.

When it's all said and done, sometimes you just have to give credit to the other guys, and the Chargers came out and made more plays in the second half than the Chiefs did, and that ultimately proved to be the difference.

2. Eric Berry made his season debut

There was intrigue all week as to whether or not this would be the week.

The hype only grew as we got closer to the game, and then it was made official, Eric Berry would make his season debut in front of Chiefs Kingdom at Arrowhead Stadium on Thursday night.

The first time his name was called the stadium went crazy, but as Chiefs' coach Andy Reid said after the game, Berry would be on a "pitch count," and ended up only playing the first half.

He finished with six tackles, including a few in which he looked like the Berry we've come to know as he came flying downhill to beat the block and make the tackle for no gain—one of which came inside the red zone inside the five-yard line.

3. Steve Nelson's interception got things going

On the second play from scrimmage for the Chargers' offense, cornerback Steve Nelson gave an already-electric crowd more to cheer for as he picked-off Chargers' quarterback Philip Rivers' first pass of the game.

It was Rivers' 7th interception in his last five games at Arrowhead Stadium.

On the play, Rivers attempted a deep shot down the middle of the field to Tyrell Williams, but Nelson was able undercut the ball, which hung up for a bit, and he dove to make the interception.

It was a fantastic play that gave the Chiefs the early momentum.

Rivers would ultimately respond, finishing 26 of 38 for 313 yards with a couple of touchdowns and a couple of interceptions.

4. Patrick Mahomes didn't waste any time giving us some of his magic

It was already crazy through the first 13 weeks of the NFL season, but at some point, you just shake your head and laugh when you see what 23-year-old Patrick Mahomes is capable of on a football field.

And we saw early against the Chargers. 

Mahomes led the Chiefs on a 10-play, 49-yard touchdown drive following Nelson's interception that had him complete two third-down passing attempts with two fantastic, albeit different, kinds of plays.

First, facing a third-and-5 from the Chargers' 21-yard line, Mahomes escaped the pocket because of some pressure and then he reversed field a couple of times before running to the near sideline and firing a dart to Tyreek Hill, who had crouched at the first-down marker along the sideline.

Then, a few plays later, Mahomes threw a perfectly-placed laser across the middle to Travis Kelce on third-and-5 for a gain of seven yards to the Chargers' five-yard line, but as great as those two third-down plays were, they were nothing compared to the touchdown throw just a couple of plays later.

Once again, Mahomes left the pocket and rolled to his right, surveying the receivers running all across the end zone and then when it looked like he'd just throw it out of bounds and live to see another play right along the sideline, Mahomes flipped it to a streaking Demarcus Robinson for a touchdown.

Robinson seemingly came out of nowhere, but just like that, the Chiefs were on the board and turned a Chargers' turnover into seven points.

5. Dee Ford gets the sack to stifle the Chargers' second offensive drive

The Chargers' second offensive drive didn't go much further than the first.

The Chiefs were able to get another negative play as outside linebacker Dee Ford, who is having the best year of his career, ran a little inside move on second down coming off the right side, and then countered back outside by spinning out of it right into the arms of Philip Rivers, who was trying to leave the pocket. 

The play resulted in a loss of seven yards and forced the Chargers into a third-and-long situation.

On that third down, Chris Jones split a double-team and got a huge hit on Rivers, who barely got the ball off as it fluttered up and was caught by tight end Antonio Gates, who was quickly tackled by Berry.

6. Mahomes gave a rookie his first career touchdown

The Chiefs' second offensive drive was as successful as the first one—resulting in a touchdown pass from Mahomes—capping-off a 10-play, 80-yard drive, but this one went to a new target in undrafted rookie running back Darrel Williams.

It was Williams' first career touchdown in just his fourth career game in which he's been active, and he also became the 11th different player to catch a touchdown this season from Mahomes.

The play, which came on second-and-10 from the Chargers' 11-yard line, was a screen to the far side of the field, and it saw center Mitch Morse out in front and make the key block that allowed Williams to turn up field and get into the end zone.

Just like that, the Chiefs had quickly taken a 14-0 lead.

7. Chris Jones had a huge night, set an NFL record

Early in the second quarter, Chris Jones was able to chase down the less-than-fast Rivers from behind for a sack, and that made it 10-straight games that Jones had brought down an opposing quarterback.

With that play, he became the only player in NFL history to record a sack in 10-straight games in the same season.

Jones added another 1.5 sacks later in the game and finished with eight quarterback hits, which ties for the third-most in the NFL for a player in a game since the stat started being kept in 2006.

The third-year player out of Mississippi State has steadily improved in each of his first few seasons, but he's had a breakout season in which he currently ranks second in the NFL with 14 sacks.

8. Kendall Fuller made a phenomenal catch for an interception in the end zone

Late in the first half and with the Chargers threatening to tie the game as the Chiefs were holding a 14-7 lead, Rivers threw an ill-advised pass on second-and-10 from the Chiefs' 11-yard line off his back-foot with pressure in his face and in the direction of Tyrell Williams.

The result was Rivers' 8th interception in his last five games at Arrowhead Stadium, and his second of the first half.

On the play, Rivers wasn't able to step into his throw because of the pressure from veteran Allen Bailey, but on the back end, cornerback Kendall Fuller made a fantastic play to jump up and high-point the ball along the back of the end zone while falling down in bounds just inches from the white line.

It ultimately took points off the board and helped preserve the Chiefs' lead going into halftime.

9. Kelvin Benjamin got his first reception in a Chiefs' uniform

Early in the second half, the newly-signed Kelvin Benjamin gave us a glimpse of what he could bring to the Chiefs' offense—hauling in a back-shoulder thrown from Mahomes for a gain of 17 yards.

The play, which saw Benjamin utilize every bit of his 6-foot-5, 245-pound frame, set up one of Damien Williams' two scores on the day.

10. Damien Williams had another solid performance

Statistically speaking, the performance we saw from Damien Williams on Thursday night was the best of his career. He finished with 123 total yards from scrimmage, which came on just 16 touches (7.7 yards-per-touch), and he also had the two rushing touchdowns.

Late in the game, Williams showed some physicality to his running style as well as he was running through would-be tacklers en route to the Chiefs' longest drive of the season—a 13-play, 80-yard scoring drive that took 7:55 off the clock and gave the Chiefs a 14-point lead with less than eight minutes to go in the game.

But Rivers would then lead the Chargers down the field on two touchdown drives that saw him convert two key fourth downs—one via a holding penalty on Nelson, and the other via a strike down the middle of the field to Travis Benjamin for a gain of 26 yards.

All of it led to a 1-yard touchdown pass from Rivers to receiver Mike Williams with just four seconds left in the game, and then the Chargers decided to go for the two-point conversion to try and win the game, and once again, Rivers would find Williams standing all alone in the end zone.

And with that, the Chargers snapped a nine-game losing streak to the Chiefs, who despite the loss, still control their fate in regard to the AFC West division title and the AFC's No. 1 overall seed.

If the Chiefs win their next two games—on the road at Seattle and then home against Oakland—they will still win the division and hold the AFC's No. 1 overall seed.