Over at the world wide leader, Mike Sando took some time to break down Justin Smith's sack totals based on the quarter of a given game (thanks to Offensiveinterference for the links in the Nuggets). The idea of Sando's post was to figure out when Justin Smith and other players were getting their sacks quarter-by-quarter. The query of the post was whether this dealt with the relentless nature of a player or other factors.
As would be expected, the numbers tell you when Smith and others got their sacks, but they don't answer why they got their sacks when they got them. Since 2008, Justin Smith has 21.5 sacks. In that time, 8.5 have come in the fourth quarter or overtime, which is 22nd among 99 qualifying players. 49ers OLB Parys Haralson was highest in the NFC West and seventh overall among players with at least ten sacks in fourth quarter sacks.
Does anybody see any reasons for this, or is there more research to be done? Sando seems to think the numbers don't provide definitive answers, but wouldn't some research into the specific games involved potentially answer that question. Justin Smith is a beast for the 49ers whenever he's getting his sacks. Even when he's not getting sacks, his ferocious pass rushing skills have led to plenty of QB hurries over the years.
I'd be curious to know how sack totals are correlated to the score of the game and the performance of the opponent. After all, if a team finds itself in a big hole early, they might feel the need to pass at a greater rate, which opens the door for more sacks. It seems fairly obviously, but maybe I'm missing something else.