Quarterbacks around the NFL have been putting up some eye-popping numbers this season. 

For instance, through four weeks, there are still four quarterbacks who are currently on pace to break Peyton Manning's record for most passing yards in a season (5,477). Including those four, there are seven quarterbacks who are on pace to crack 5,000 passing yards this season, which is an absurdly high number when you consider that only nine quarterbacks have ever hit that number in NFL history. 

Oh, and there's been a lot of points. As a matter of fact, the Chiefs (580) and Rams (560) are both on a pace that would make them one of the top-three scoring teams in NFL history.    

San Francisco cornerback Richard Sherman has a theory on why this offensive explosion is happening and he thinks it's because the NFL decided to enact a bunch of rules in 2018 that impedes the defense's ability to play football, especially when it comes to hitting the quarterback. 

"You can't touch him. You can't tackle him. You can't hit him high, can't hit him low. You can't knock him down to the ground hard . . . all that," Sherman said this week, via ESPN.com. "You can't hit a receiver too high; you can't hit him low; you can't push him. You can barely press him. It's making it really difficult on teams to combat it because every rule in the book is designed to make sure you don't get them stopped."

According to Sherman, the NFL is all but legislating defensive play out of the game. 

"They're just trying to make it impossible for guys to play defense," Sherman said. "It's an interesting league we play in."

One of the most notable trends this year has been the play of your average quarterback. As noted by FootballPerspective.com, quarterbacks in the league have an average QB Rating of 92.3 this season, which is almost better than Joe Montana. 

 Sherman has definitely taken notice of stats like that. 

"This is what the league wanted," Sherman said. "They want record passing numbers. You've got an average quarterback; the average quarterback's passer rating is like 92 and that used to be Hall of Fame numbers, and now it's not Hall of Fame numbers. That's the average quarterback."

If the NFL wants to protect quarterbacks, Sherman thinks they should just go all-in. 

"My suggestion was to put flags on the quarterbacks," Sherman said. "If you don't want them touched, don't want them knocked down, these [defensive ends] and [defensive tackles] and linebackers have long arms so they'll be able to snatch these flags off without touching these guys half the time so whenever they're ready to move to that, I'm sure defenses will appreciate it."

For a defender, the only thing harder than trying to follow the new rules is trying to follow them while you're injured, which is what Sherman might have to do Sunday. After missing the 49ers Week 4 game with a calf injury, Sherman has been listed as questionable for this week's game against the Cardinals. If he does play, Sherman could be slightly hobbled by his sore calf.