By and large, the statistics in this post are coming from Pro Football Focus. They have signature stats that are more conventionally comprehensible (like how many QB hurries a lineman gives up). In addition, though, PFF provides weekly "grades" that are overall numbered scores. You can read about their grading process HERE. Positive numbers are good while negative numbers are bad. Anything above +1 is a really good game; anything below -1 is quite a bad game. The grade is a composite grade of different smaller grades (like "pass blocking"). I will typically highlight the strengths and/or weaknesses of a particular performance by looking at these composite grades.
The reason this post is so late in the week is due to some personal issue; as a consequence, I wasn't able to watch the game against the Saints live. I watched it already knowing the outcome and the talking points concerning what happened. When one watches a game this way, it changes the way one evaluates it as it is ongoing. 23-20 seemed a bit lower than I expected, so I assumed that the pass rush was disrupting Drew Brees left and right. Upon watching the game, I think it's fair to say that I was a bit off. There were some nice moments, but by and large, Brees had a decent amount of time. He was occasionally hurried (in particular, Justin Smith generated a nice 5 hurries and Patrick Willis 3), but not frequently hit.
So, I thought it might be instructive to look at the pass rushing output of our three main pass rushing OLBs (NB: Dan Skuta seems to occasionally come out of nowhere with a nice pass rush - but, by and large, he is more of a run stopper).
Ahmad Brooks: -1.8 PFF Pass Rush, 1 QB Sack, 0 QB Hits, 0 QB Hurries
The big story with Mr. Brooks this game is obviously the penalty that, basically, handed the Saints the game. From a purely pass rushing perspective, though, it was some fine work. He sped right past the tackle and into Brees. Unfortunately, this was nearly all he did on the day. Ending the game with 1 sack on 32 pass rush plays, he was inconsistent in getting to the QB. Thus, PFF gave him the dreary -1.8 score for his pass rush attempts. He did have a nice day otherwise, earning a 1.6 grade in pass coverage and a 0.3 in run defense.
Aldon Smith: 0.3 PFF Pass Rush Grade, 0 Sacks, 1 QB Hit, 2 QB Hurries
In nearly the same amount of pass rush plays as Ahmad Brooks (30 to Brooks' 32), Aldon tripled the time he disrupted the QB with his 1 hit and 2 hurries. What was encouraging for Aldon was his greater presence on the field: he ended up playing in 44 total plays. And, while working through the rust, Mr. Smith was able to contribute at a level most people likely expected from him coming back. His 0.3 pass rush score is an encouraging starting point as he looks to close out the season strong. The key now will be turning these hurries into sacks. This is, of course, something he has been historically quite good at.
Corey Lemonier: -0.4 PFF Pass Rush Grade, 0 Sacks, 0 QB Hits, 0 QB Hurries
Simply based upon the conventional pass rush numbers, this game looked like a bit of a dud for Mr. Lemonier. Heck, he didn't even have a tackle or an assist. But, there is one number to keep in mind here: 5. Corey was only on the field for 5 plays against the Saints, 4 of which were pass rush plays. This seems a bit odd to me. Save against the Jaguars, Lemonier was rushing the passer quite well. So well, in fact, that he deserves more playing time. At one point in the game, the 49ers had Brooks, Smith, Lemonier, and Justin Smith all in, ready to rush the passer. This is, I think, an effective group of guys in a passing situation. Our defense loves to get pressure with four guys while everybody else drops back into coverage. I hope Lemonier's role expands a bit more in the coming weeks.