San Francisco 49ers at Los Angeles Chargers
Thursday, August 20, 2026
10:00 PM ET, SoFi Stadium
Thursday night’s late window preseason game at SoFi Stadium has one of the most straightforward Under setups on the entire Week 2 board.
The Chargers are 1.5-point home favorites with a total of 39.5. Both numbers opened right where they sit now, which is unusual for a preseason game. When neither the public nor sharp money can nudge a line off its opening number, it typically means both sides are looking at the same fair value. In this case, the fair value points to a low-scoring game with backups on the field for most of the night, and there are enough situational factors pushing in the same direction that the Under stands out.
Let’s start with Week 1.
The Chargers were dominant last Thursday in Houston, winning 27-7. That’s a combined 34 points, well under their game’s total of 36.5. The 49ers, meanwhile, lost at home to the Titans 19-13. That’s a combined 32 points, well under their game’s total of 39.5. Both teams opened preseason with games that finished below the number. Preseason coaching identity carries over from week to week, and neither of these staffs is running a track meet offense.
The joint practice this week is the other big factor.
The two teams have a joint practice scheduled at the Chargers’ facility in El Segundo on Tuesday, August 18. When two teams practice together in the days leading up to a preseason game, the starters typically get their real competitive work done at the practice rather than in the game itself. Kyle Shanahan is famously conservative about preseason snaps for his veterans, and Jim Harbaugh does something similar with his top players. Brock Purdy is likely to play a series at most. Justin Herbert is likely to play a series at most. From there, both offenses are being run by backup quarterbacks trying to hold onto roster spots.
Speaking of backups — the Chargers’ QB2 competition is between Trey Lance and DJ Uiagalelei, neither of whom has demonstrated the ability to move an NFL offense consistently. The 49ers’ backup room isn’t much better. When both teams are cycling backup quarterbacks through the second and third quarters, points tend to dry up quickly.
The coaching-staff crossover is worth mentioning because it changes the dynamic in a real way. Mike McDaniel is in his first year as the Chargers offensive coordinator after being fired by Miami. What most people don’t remember is that McDaniel spent 2017 through 2021 on Kyle Shanahan’s staff in San Francisco, including as the offensive coordinator during the 49ers’ 2021 NFC Championship run. He knows the 49ers system inside and out, and he’ll be facing the very team he cut his teeth with. On the flip side, Jim Harbaugh coached the 49ers from 2011 to 2014, going 44-19-1 with three playoff appearances and a Super Bowl XLVII appearance. Two head coaches on the Chargers sideline with deep 49ers ties, going against a 49ers team that runs a similar scheme. That’s a recipe for a lot of familiarity, minimal surprise, and slow, methodical play.
Both teams also have injury concerns that suppress preseason scoring. The Chargers are dealing with left tackle Rashawn Slater (leg), cornerback Tarheeb Still (didn’t practice last week), and running back Najee Harris (Achilles). The 49ers are missing WR Ricky Pearsall for the year (PCL surgery) and running back Kamara reverted to injured reserve this week. Injuries in preseason force even more roster-bubble players into meaningful snaps, and roster-bubble players don’t score a lot of points.
The advanced stats back the Under too. The 49ers had just 20 sacks in the entire 2025 regular season, which was the fewest in the NFL — meaning even when Chargers backups have the ball, they’re not going to be running for their lives on every play. The Chargers had a 41.7% completion rate when trailing inside four minutes in 2025, which was the lowest in the NFL — an indicator that their offense struggles to sustain drives in high-pressure situations, which is exactly what preseason backups face on every possession.
I looked at the side too. Chargers -1.5 at home with Harbaugh in year three and the emotional edge of facing his former team is defensible. But the line has held firm at -1.5 all week, and preseason spreads that small can flip on any single garbage-time possession. The total gives me the cleaner path.
The Pick: 49ers/Chargers Under 39.5
