This would be in reference to the 49ers having allowed no rushing touchdowns since last season.
I'll confess to entertaining the following scenario in recent weeks:
The 49ers lead by five. The opponent has fourth-and-goal from the 1-yard line with one second remaining in the fourth quarter. The opposing team's leading rusher has 99 yards on the ground. The 49ers, having not allowed a 100-yard rusher in their last 33 games, need a victory to clinch something of importance.
That's the sort of drama 49ers fans could surely do without. I don't expect the team to face such a scenario, particularly against the Rams. But I'd love to be there if it happened.