Game facts: 49ers at Cardinals

Historically bad run defense:  The 49ers allow 193.0 rush yards per game this season (would be most allowed in a season since 1980 Saints allowed 194.1).

Mind-blowing stat:   San Francisco is on pace to allow 520 points this season (would be 2nd-most in history behind the 1981 Baltimore Colts).

Offense trending up?:  In Week 9, the 49ers gained their most total yards (486) and pass yards (393) since Week 1, 2013 against the Packers.

Tale of two halves:  Colin Kaepernick has a 118.2 passer rating in the first half this year, but a 49.9 rating after halftime.

Bad memories:  The last time he played in Arizona (Week 3, 2015), Kaepernick registered the lowest career passer rating as a starter (16.7).