Oddsmakers might be favoring the 49ers because of how they have won games recently. Bouncing back from a challenging October, the team is now on a three-game winning streak, dominating opponents with an average margin of victory of 20.7 points.
In contrast, the Eagles have secured victories with a more modest average margin of 4.8 points over their last four games, including an overtime win against the Buffalo Bills on Sunday.
Only four teams with a 10-1 record have been considered underdogs in the Super Bowl era. The most recent example was the 2019 49ers, who were 5.5-point underdogs in a matchup against the Baltimore Ravens, ultimately losing 20-17. The Eagles are now the first 10-1 home-team underdog in the Super Bowl era.
Even the 49ers' head coach finds the odds puzzling.
"It doesn't make a lot of sense to me, but I don't really know how that stuff works, so I don't really know why," Kyle Shanahan told reporters on Wednesday. "It is random."
For Shanahan and the 49ers, the upcoming game is just the next challenge on the schedule. However, a victory would bring San Francisco within striking distance of the top seed in the NFC playoff picture. The NFC powerhouses are scheduled to kick off on Sunday at 1:25 p.m. PT (4:25 p.m. ET).