The 49ers are at full strength on offense for the first time this season. Jimmy Garoppolo doesn't have to be Joe Montana with Kyle Shanahan calling plays and backed by elite weapons Christian McCaffrey, Deebo Samuel, George Kittle and Kyle Juszczyk. 

The Chargers rank 30th in scoring defense allowing 25.8 points a game. 

Fresh off their bye, the 49ers also are healthier on defense, too. This doesn't bode well for the Chargers, who remain extremely banged-up offensively.
Justin Herbert has become just a glorified game manager minus his star left tackle and without his two best wide receivers, Keenan Allen and Mike Williams. Herbert has not completed a pass longer than 20 yards during his last three games. He's also gone four consecutive games without reaching the 300-yard passing mark. 

The Chargers haven't defeated a good team yet. Their victories have been against the Raiders, Texans, Browns, Broncos in overtime and Falcons with three of those wins coming by a combined eight points. Los Angeles has been outscored by 22 points on the season.