Gore's 93rd game featured six carries for zero yards and a question: What happened?
NFL Rushing Leaders vs. 8+ Box Counts
Frank Gore averages 3.3 yards per carry against eight-plus defenders in the box (min. 20 carries). The league average is 3.2.
"The Giants took extreme measures -- measure that I have rarely seen in the National Football League," 49ers offensive coordinator Greg Roman told reporters. "It was pretty much a numbers situation. Extremely loaded boxes."
A loaded box area features more defenders near the line of scrimmage than the offense has available to block them.
The Giants did pack eight or more defenders into the box on 19.2 percent of plays against the 49ers, up from 9.2 percent against previous opponents, according to Jason Starrett of ESPN Stats & Information.
Gore averages 2.5 fewer yards per carry against eight or more defenders in the box than he averages against standard seven-man boxes. That drop exceeds the 1.4-yard differential for all runners. While Gore averages 3.3 yards per carry against eight or more in the box, right around the 3.2-yard NFL average, teammate Kendall Hunter leads the league with a 6.1-yard average on these runs (min. 20 attempts).
NFL Rushing Leaders vs. 7- Box Counts
Gore averages 5.8 yards per carry against seven or fewer defenders in the box (min. 70 carries). The league average is 4.6.
The Giants had good reason for loading up against the 49ers' running game. Their run defense has been much more effective this season -- overall and relative to other teams -- when assigning at least eight defenders to the box.
Opponents have carried 197 times for 997 yards and three touchdowns when the Giants had seven or fewer in the box. That works out to 5.1 yards per carry, which ranks 26th in the league. But the Giants rank sixth in yards per carry allowed (2.3) when committing eight or more to the box. Opponents have carried 42 times for 97 yards and seven touchdowns on these runs, which include carries near the goal line.
Overall, the Giants allow 2.75 fewer yards per rush when committing at least eight defenders to the box. That is the third-largest differential in the league this season behind those for the Detroit Lions (minus-3.43) and New England Patriots (minus-3.88).
Which Teams Use 8+ Defenders the Least
The chart at the bottom ranks NFL teams by fewest yards per carry allowed with no more than seven defenders in the box. I've also included averages with eight or more in the box, plus a column showing differential. I've rounded off figures to the tenth. Rankings reflect more specific calculations, explaining why Indianapolis, Houston and Cleveland have the same averages but different rankings.
Teams with many more plays near the goal line might produce skewed results. That's why I've ranked the chart by fewest yards per carry allowed with seven or fewer in the box. Teams faring better against the run in these situations tend to have greater flexibility in coverage. The 49ers' strength in this area has taken pressure off their secondary, without question.
The 49ers have used more than seven in the box against only nine rushing plays this season, fewest in the NFL. The average is 47.4 for the other 31 teams. The Seattle Seahawks and Arizona Cardinals have been much more likely than the 49ers or St. Louis Rams to use eight-plus defenders in the box on running plays.