Houston’s J.J. Watt sacked Andrew Luck three times on Sunday, bringing his season sack total to 19.5. Entering 2012, Bruce Smith was the single-season record holder for sacks by a defensive lineman in a 3-4 scheme with 19 in 1990. The sack has only been an official statistic since 1982, but since the 3-4 only entered the NFL in the mid-’70s, we can be pretty sure that Watt is now the all-time record holder.

The tables below show the single-season leaders by various defensive players in 3-4 and 4-3 schemes from 1982 to 2011.

Let’s start with a look at the most sacks by a 3-4 defensive end:

As you can imagine, 3-4 defensive linemen don’t rack up many sacks. Bill Pickel, a nose tackle for the Raiders in the ’80s, recorded 12.5 sacks in both ’84 and ’85, making him the only 3-4 tackle to record more than 12 sacks in a season. Karl Mecklenburg, with 13 sacks for the Broncos in ’85, remains the only inside linebacker in a 3-4 with more than a dozen sacks.

Of course, 3-4 outside linebackers get all the glory in that scheme. San Francisco’s Aldon Smith has 19.5 sacks so far in 2012 with two games remaining, but here were the leaders prior to 2012:

What about 4-3 defensive ends?

And 4-3 defensive tackles:

4-3 outside linebackers rarely rack up huge sack numbers. In fact, Denver’s Von Miller, who has 16 sacks this year, is already the record holder in the official sack era. Derrick Thomas (14.5 sacks in 1992, 13 in 1996) in Kansas City, Washington’s Ken Harvey (13.5 in ’94) and Cleveland’s Jamir Miller (13 in ’01) are the only other 4-3 outside linebackers with more than twelve sacks in a season since 1982. (Of course, Thomas also had a 20-sack season a 3-4 outside linebacker.) Charlie Clemons, with 13.5 sacks in 2001, is the record holder among 4-3 middle linebackers.