Could Aaron Donald be the best defensive tackle ever?
Though Pro Football Focus wasn't around in the days of "Mean" Joe Greene or Merlin Olsen, we have been grading games since 2006, and have 13 seasons worth of play-by-play grading in our database. All of that data indicates that it would be difficult for any pass-rusher to scale higher peaks than the ones Donald is ascending right now.
We can't definitively put Donald in the context of the older all-time greats, but we can quantify how much better Donald is than any defensive tackle we have seen over the last decade-plus of action. In doing that, we can put into focus the enormity of what he's doing and the difficulty of anyone surpassing him.
Donald isn't just the league's best interior pass-rusher ...
When focusing only on interior pass-rushers, the gap between him and the field is quite wide. Donald leads Geno Atkins and Fletcher Cox, the second- and third-most productive interior pass-rushers since 2014, by 79 and 83 pressures, respectively. To provide context, those figures would lead the league more often than not in a single season.
Donald has out-graded every interior defensive lineman by a comfortable margin in every season since 2015. That includes league-high overall grades of 93.0 in 2015, 92.6 in 2016, 94.4 in 2017 and a career-high 95.0 a season ago. He has also posted the best pass-rushing grade among all interior D-linemen in those seasons, as well.
But that's not where his dominance ends.