The Kansas City Chiefs and the Los Angeles Chargers faced each other on Sunday, and the result couldn't have been more surprising. The Chargers pulled an upset in the closing stages of the game, adding more spice to the growing rivalry between Patrick Mahomes and Justin Herbert.The win had a special taste for Los Angeles, as the team was not only able to beat Mahomes but they also had confirmation that their quarterback could be as good as Patrick. Justin Herbert had another fantastic exhibition and his game-winning touchdown was proof of how mature he is to the pro level.Fans went crazy on Twitter after the biggest win of Justin Herbert's career:Los Angeles Chargers@chargersGOTTEM5:10 PM · Sep 26, 2021114643522GOTTEM https://t.co/bUViyeUop5Sportskeeda Pro Football@SKProFootball#Chargers win against the #Chiefs 🔥The former AFC West champions are now at the bottom of the division 👀5:12 PM · Sep 26, 202182#Chargers win against the #Chiefs 🔥The former AFC West champions are now at the bottom of the division 👀 https://t.co/UtEWuJnkBpShea Serrano@SheaSerranothe chargers are out of control lol5:01 PM · Sep 26, 202135720the chargers are out of control lolChris Hayre@chrishayreThe Chargers will start 1-0 in the AFC West for the first time since 2014.5:16 PM · Sep 26, 202175446The Chargers will start 1-0 in the AFC West for the first time since 2014.The Volume@TheVolumeSports“There is not a quarterback in the league that makes it look easier than Justin Herbert.” — Hear from @ColinCowherd following Chargers win over Chiefs:5:16 PM · Sep 26, 20212011426“There is not a quarterback in the league that makes it look easier than Justin Herbert.” — Hear from @ColinCowherd following Chargers win over Chiefs: https://t.co/HBDmza1yPgSkip Bayless@RealSkipBaylessMahomes gets away with more potential interceptions than any QB I've ever seen. Will try anything - and often make it work. But today, in the end, tossed up an awful INT over Kelcey's head that opened the door for the Chargers' victory ... just as his INT at Baltimore did.5:12 PM · Sep 26, 20211980163Mahomes gets away with more potential interceptions than any QB I've ever seen. Will try anything - and often make it work. But today, in the end, tossed up an awful INT over Kelcey's head that opened the door for the Chargers' victory ... just as his INT at Baltimore did.Ari Meirov@MySportsUpdateAFC West standings:#Raiders: 3-0#Broncos: 3-0#Chargers: 2-1#Chiefs: 1-2Just like we all expected.8:49 PM · Sep 26, 20216108589AFC West standings:#Raiders: 3-0#Broncos: 3-0#Chargers: 2-1#Chiefs: 1-2Just like we all expected.Los Angeles Chargers@chargerswe love this song5:26 PM · Sep 26, 202194852487we love this song https://t.co/BxiarBiStMDov Kleiman@NFL_DovKleimanThose #Chargers-#Chiefs game are going to be amazing for years to come.Herbert 4 TDs, 0 INTs.Mahomes 3 TDs, 2 INTs, including one late in 4thBack in July: “Watch out for Justin Herbert next year.” @PatrickMahomes : “I’ll see it when I believe it.”5:13 PM · Sep 26, 20211334383Those #Chargers-#Chiefs game are going to be amazing for years to come.Herbert 4 TDs, 0 INTs.Mahomes 3 TDs, 2 INTs, including one late in 4thBack in July: “Watch out for Justin Herbert next year.” @PatrickMahomes : “I’ll see it when I believe it.”https://t.co/11WI4uxyoCNFL on CBS 🏈@NFLonCBS"This is...Justin Herbert's...biggest win of his career by far, no question." - Tony Romo @chargers5:16 PM · Sep 26, 20212361225"This is...Justin Herbert's...biggest win of his career by far, no question." - Tony Romo @chargers https://t.co/6QFX9AhzXEDan W.@ChargersHomer"We're fortunate enough to have a gangster quarterback." - #Chargers HC Brandon StaleyJustin Herbert IS that dude.5:39 PM · Sep 26, 2021970105"We're fortunate enough to have a gangster quarterback." - #Chargers HC Brandon StaleyJustin Herbert IS that dude.How good can the Chargers be in 2021?The Chargers gave a fantastic display of power by beating the Chiefs at Arrowhead Stadium on Sunday. That was the biggest win of Justin Herbert's career. It is also important for playoff purposes, as Los Angeles remains a single game away from the division leaders Las Vegas Raiders and Denver Broncos. Meanwhile the Chiefs have a negative record and sit at the bottom of the division.It's a much more improved team from 2020, especially because the coaching staff does not find different ways to lose a game every weekend. If not for two silly penalties in Week 2 against the Dallas Cowboys, Los Angeles would be another 3-0 team in the AFC West. They are still well positioned to play in January should they continue to improve their game.Brandon Staley is a happy man in Los AngelesIt all depends on Justin Herbert. Can he take another step further and become an elite quarterback? The early signs are positive but he still needs to deliver on a consistent basis. Beating Mahomes is a fantastic start for Herbert.For the Chiefs, there has to be some level of concern. Kansas City is expected to win a number of games this season and book a playoff berth. However, it doesn't seem like the pass protection has improved much from last year, and the defense is shaky. There are a lot of corrections needed if this team wants to reach the third consecutive Super Bowl.