San Francisco’s run defense is really struggling. Six weeks in a row it’s allowed a 100-yard rusher, and half of those guys are players who weren’t even starters on opening day – Fozzy Whittaker (who got his yards off the bench), Christine Michael and Jacquizz Rodgers. Rodgers wasn’t even on a roster on opening day.

I checked into the historical numbers. Since the NFL moved to the 16-game schedule in 1978, this has happened only four other teams. No defense has done it seven weeks in a row, and the 49ers won’t be the first (they have a bye in Week 8).

The 49ers almost allowed two 100-yard rushers on Sunday. Peyton Barber busted a long touchdown late to finish with 84 yards.

Some, by the way, like to bemoan that teams don’t run the ball like they used to. But they also don’t DEFEND the run as well. Of these five teams that have allowed 100-yard rushers six weeks in a row, all but one have come in the last 10 years. It didn’t happen at all in the ‘80s or ‘90s.

1979 OAKLAND RAIDERS
PlayerAttYardsAvgTD
Paul Hofer, S.F.131068.20
Earl Campbell, Hou.321073.31
Mike Williams, K.C.281093.90
Rob Lytle, Den.181025.71
Chuck Muncie, N.O.211286.11
Mike Pruitt, Clev.201497.52
2006 ST. LOUIS RAMS
PlayerAttYardsAvgTD
LaDainian Tomlinson, S.D.251837.32
Larry Johnson, K.C.271726.41
Maurice Morris, Sea.211245.90
DeAngelo Williams, Car.201145.70
Frank Gore, S.F.211346.41
Edgerrin James, Ariz.261154.40
2007 CLEVELAND BROWNS
PlayerAttYardsAvgTD
Willie Parker, Pitt.271094.00
Rudi Johnson, Cin.231185.10
LaMont Jordan, Oak.291214.21
Willis McGahee, Balt.141047.40
Sammy Morris, N.E.211024.90
Ronnie Brown, Mia.191015.30
2013 CHICAGO BEARS
PlayerAttYardsAvgTD
Eddie Lacy, G.B.221506.81
Reggie Bush, Det.141057.50
Ray Rice, Balt.251315.21
Benny Cunningham, St.L.131098.41
Adrian Peterson, Minn.352116.00
DeMarco Murray, Dall.181468.10
2016 SAN FRANCISCO 49ERS
PlayerAttYardsAvgTD
Fozzy Whittaker, Car.161006.30
Christine Michael, Sea.201065.32
Ezekiel Elliott, Dall.231386.01
David Johnson, Ariz.271575.82
LeSean McCoy, Buff.191407.43
Jacquizz Rodgers, T.B.261545.90

—Ian Allan