The Los Angeles Chargers suffered one of the worst injuries of the preseason when left tackle Rashawn Slater tore his left patellar tendon. The good news for head coach Jim Harbaugh is that Joe Alt aced his first test stepping in for Slater on the blind side.
In fairness, it's not as if Alt came into the NFL with modest expectations. He was the No. 5 overall pick in the 2024 draft after a stellar collegiate career at Notre Dame. Alt played most of his snaps with the Fighting Irish at left tackle, but the Chargers selected him with the idea that he possessed the versatility to move to the right side due to Slater's presence on the roster.
That worked well for Harbaugh and his staff during Alt's rookie season. It was still a slightly open question as to how he would handle moving back to the blind side in Week 1. Alt answered that question with a dominant performance against a talented Chiefs' front.
Joe Alt looks like the NFL's next superstar after left tackle debut vs. Chiefs
The Chargers came into the game with a clear game plan to throw the ball early and often. That only makes Alt's stellar play more impressive: He did not allow a single pressure on the evening and posted a PFF grade of 91.4 as a pass blocker. Kansas City's defensive coordinator Steve Spagnuolo challenged the Chargers' front with a lot of blitz packages, but Alt did not put a step wrong in his team's narrow victory.
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Joe Alt: 91.4 pass-blocking grade in his first game at LT ⚡
Check out all of the grades from Chargers-Chiefs ⬇️
Alt looked particularly impressive when he was tasked with going against All-Pro defensive lineman Chris Jones on multiple reps. He stymied Jones with a solid combination of hand power and quick feet on the perimeter. If Alt can keep a player of Jones' caliber quiet, there's no reason he can't stop any other lineman in the NFL as the regular season rolls along.
It's worth noting that Slater's injury still harms the overall quality of Los Angeles' offensive line. There's a steep dropoff of performance at right tackle, since Alt can't be deployed at that spot any longer. Trey Pipkins has the talent to be an average starter, but no one should reasonably expect the former third-rounder to be anything more than that.
The takeaway for the Chargers after Week 1 is that Alt now profiles as a player who can give them All-Pro caliber play at left tackle. Few teams in the league can survive such a catastrophic injury at a premium position and maintain competence. Alt's brilliance against the Chiefs proves that the Chargers can do that and more at the left tackle position; when Slater returns next season, this offense might be ready to fully explode.