Aaron Donald will one day go down as arguably the greatest defensive tackle in NFL history. After a remarkable, record-setting 2018 season, he’s moved one step closer to punching his ticket to Canton when it’s all said and done.

With 20.5 sacks (a defensive tackle record) and an NFL-high 25 tackles for loss, it was truly one of the best seasons ever by a defensive lineman. He isn’t the only Rams defender to put together an all-time great campaign, though.

Robert Quinn had one of his own in 2013 when he was named the PFWA Defensive Player of the Year. In Pro Football Focus’ eyes, that was the best season by an edge defender in the site’s history.

Donald’s overall grade of 95.0 was tied for the highest ever at any position and the best ever by an interior defender. Quinn’s grade of 93.6 is the best in PFF history by an edge defender, too.

Here’s what PFF wrote about Donald’s incredible 2018 season.

There are a number of Aaron Donald seasons that would have been good enough to take this spot. If it weren’t his 2018 season, it would have been his 2017 season, which he finished with a 94.4 overall grade; if it weren’t his 2017 season, it would have been his 2015 season, which he finished with a 93.0 overall grade. You get the point. Donald’s 2018 season surpassed what we thought was possible — even for him — for a player on the defensive interior. His 95.0 overall grade is the best single-season grade ever recorded by a player at the position; his 23.0% pass-rush win rate and his 10.1 pass-rush productivity both ranked first among interior defensive lineman last year.

Quinn didn’t put up the numbers that Donald did, but his 2013 season was one of the best ever by a Rams pass rusher – at least in the era since sacks became an official stat. He was a nightmare for left tackles to block, consistently getting around them with his speed and phenomenal technique.

To this day, Robert Quinn’s outstanding 2013 season still holds the best overall grade ever recorded by an edge defender, and for good reason. Playing 99.4% of his pass-rush snaps from the right side, Quinn was almost unblockable all season long and ended the campaign with 19 sacks, 21 hits and 51 hurries from his 478 pass-rush snaps. His 91 total pressures are still tied for the sixth-most ever recorded by an edge defender over the course of a single season; he led the league that year in pass-rush productivity and also ranked fifth among his peers in run-defense grade (84.2).

One other Rams player made PFF’s list of the best single-season grades at each position, and it’s Eric Weddle. Only, his season didn’t come as a member of the Rams. It was in 2012 with the Chargers, earning an overall grade of 92.2.

Donald and Quinn are two of the better pass rushers the Rams have had in recent memory, it’s just unfortunate that injuries limited Quinn in St. Louis and L.A.