With the way the rules have changed to favor the offense, it won't be too long before Manning's mark falls.

In today's NFL, a player like Marino, Favre or Manning in their prime would throw for 40 TDs a year for 8+ years...and QBs are able to play 15+ seasons far more often today than they were a few decades ago thanks to better conditioning and preparation.

Rodgers had close to 200 TDs in 5.5 seasons. What makes anyone think that 500 is such an unreachable mark in today's NFL?