The 49ers retooled their pass rush this past offseason, trading away a second-round pick in 2020 for Chiefs defensive end Dee Ford and using the number two overall pick in the 2019 draft on Ohio State defensive end Nick Bosa, who many widely considered the best pass rusher in the draft. Ford got a five-year, $87.5 million dollar contract, has produced early and often and looks to be a formidable piece of the pie.
However, Bosa has been every bit as advertised and has mostly quieted the skeptics about the concerns over a lack of collegiate production and injury history. The entire defensive line played a critical role in their first three games, but Bosa is arguably having the biggest impact on the first three games, and that’s remarkable given the production and effect the other former first-round picks are having. For now, we’re only going to focus on the ways Bosa effects the game.
Pass rush productivity
While Bosa doesn’t have the flashy stats that fans like to see like sacks (he has two according to Pro Football Focus (PFF) and one according to official NFL stats), he currently has the highest pass-rush win rate among the 2019 first-round edge defenders with a 36.1% win rate. For simplicity, the win rate is defined as the snaps where a pass rusher wins his rush against the blocker in front of him to get into the backfield.
First-round edge defenders pass-rush win rates on passes thrown 2.6+ seconds after the snap (Min. 20 snaps) through Week 3, per @PFF.— Austin Gayle (@PFF_AustinGayle) September 26, 2019
- Nick Bosa (36.1%)
- Josh Allen (26.1%)
- Brian Burns (23.7%)
- Clelin Ferrell (11.8%)
- Montez Sweat (11.4%)
In college, PFF graded him with a career win rate of 24.5%. For perspective, the top edge rushers in a given draft are only winning 17-18% of the time. And there is a strong correlation between pass-rush productivity at the collegiate and NFL levels that states that if the defender was highly productive in college, he would also be in the NFL:
“Doing simple correlation analysis, we find that per-snap pass-rushing grades at the college level correlate at a rate of 0.69 with grades at the NFL level, meaning that roughly half of the variance in how a pass-rusher performs at the pro level (should he get to 250 pass-rushing snaps) can be explained by the variance in how he graded as a college pass-rusher.”
Through three games, Bosa has a pass-rush productivity rate of 14.0, meaning he’s recording some type of hit, hurry, sack, or pressure, on 14% of his pass-rush snaps, good enough for third in the NFL ahead of such names as Miles Garrett, Cameron Wake, Danielle Hunter, and Khalil Mack. He leads the 49ers in total pressures with 17, good enough for ninth in the NFL, and has done so in less pass-rushing snaps than everyone in the top ten of total pressures.
Where he wins
Multiple pass rush moves
In college, Bosa won in the trenches with a variety of pass rush moves at his disposal. Bosa is listed at 6-foot-4-inches and 266 pounds, but he doesn’t have the wingspan that the rest of the 2019 first-round edge rushers have. Instead, he relies more on a combination of strength and technique with his compact frame.
Bosa can win with a variety of moves to the outside. His main pass rush move to the outside is the “double swipe” or what’s known as the “side scissors.” The double swipe is a great move to counter an aggressive punch by the offensive lineman and involves simply swiping the hands or arms away from the tackle who’s attempting to punch the defender.
Bosa usually executes the move with a hard jab step to the inside (power step). The jab step gets the tackle to commit by “punching,” and this is where the move becomes effective. With the tackle committed and overextended, Bosa angles back outside and instantly swipes away the hands of the tackle, throwing the tackle off-balance. The technique shows Bosa’s quick hands and feet.
Usually, if Bosa is winning outside on the edge for most of the game, he’ll switch things up by rushing inside, which he can do just as effectively.
Here, the double swipe can be just as effective for him inside as it is on the outside. The primary objective of the double swipe is to get the tackle off balance. Bosa attacks the half-man relationship with a subtle jab step as the tackle lunges forward to punch him. His rush probably got the tackle to anticipate a speed bull (which he does effectively), and as the tackle punches, Bosa swipes away the hands of the tackle, fights through the traffic nearly finishes with the sack.
Another effective way to win inside is with his use of the “pull and club,” which is also a great way to get a blocker off-balance by moving in one direction and stunning him with another move in the opposite direction.
The pull and club move works by reacting to the tackle’s initial contact and punching or pulling the outside shoulder of the blocker. As soon as the tackle lurches forward, he’s off-balance and stops his feet as Bosa power steps to the inside while simultaneously clubbing or pinning the inside arm of the blocker as he rushes inside. Bosa has a clear path to quarterback Jameis Winston but cannot finish with a sack.
When you can’t win outside or inside, it’s sometimes just more effective to bully your opponent with your strength and leverage instead of technique and use a bull rush, converting speed to power.
In speed bull rush, the pass-rusher uses a low center and low pad level of gravity and explodes up into the blocker upon contact. Bosa dominated left tackle Alejandro Villanueva in week three with several pass rush wins where he just speed rushed and bulldozed Villanueva to the ground. Villanueva is a two-time pro bowler and seasoned NFL veteran. In two games, Villanueva allowed just three pressures. Against Bosa, he allowed six total. Bosa was recording a pressure every 3.4 passing snaps (24 pass rush snaps, seven total pressures) when facing Villaneuva.
Effect on the game
While Bosa hasn’t always finished with sacks, he has had more effect on the outcome of each game as he has been able to get pass rush wins in important moments and fluster the opposing quarterbacks by moving them off their spot and forcing turnovers or sacks.
Several times in the game’s final drive in Tampa Bay, Bosa found himself in the backfield forcing Winston to check down and keep every attempted pass in front of the defense.
Bosa didn’t play bad for his first rookie start against Tampa Bay and came through with several pressures at the right time, but he really started to have a greater effect on the games since week one, against Cincinnati and Pittsburgh.
Against the Bengals in week two, he began to show how much of a factor he can be by forcing turnovers. The game was already out of reach by this point in the second quarter with the 49ers leading 21-10 before halftime, but Bosa forced an interception on a drive the Bengals needed to get points on.
On a fire zone blitz, the 49ers are running tackle-end exchange stunt to the right with Bosa looping inside behind defensive tackle Deforest Buckner, who drew two blockers when Bosa peeled off to loop around. Nickel defender K’Waun Williams came off the edge to occupy the running back which removed three blockers as Bosa loops through the A-gap.
Bosa’s appearance in Andy Dalton’s throwing lane forces Dalton from the pocket to his right to avoid the sack. As Dalton scrambles, linebacker Kwon Alexander played his receiver with underneath leverage that Dalton doesn’t see. Bosa chases and stumbles, but it doesn’t matter, Dalton throws into the coverage and is intercepted. The 49ers would another field goal on their next drive before halftime.
We discussed the ways above that Bosa dominated Alejandro Villaneuva in the week three game against the Steelers but his best moment came on a fumble that would prevent the Steelers from working down the field. During the bye week, Bosa said “I brought power almost all day (against the Steelers). Hit them with a couple speed moves, but I knew I could get underneath him and power him, so I did.”
Bosa is out wide against Villaneuva again like he had been all game, and at the snap, he takes off on a speed bull rush directly Villaneuva. He initiates contact and explodes upward in what’s known as the “bullfork” technique. He lifts Villaneuva, drives his legs and pins Villaneuva’s arms to his body, and shoves him to the ground.
Bosa chases quarterback Mason Rudolph and grabs him simultaneously with defensive end Dee Ford. Rudolph escapes the sack momentarily, but he’s unable to get going again as Arik Armstead arrives and gets the strip-sack. Had Bosa not contained him in the pocket cut off Rudolph’s ability to escape, he may have converted a pass or scrambled for a first down.
Where he needs to improve
The one area Bosa needs to improve is in his ability to finish plays with sacks instead of losing his balance and ending up on the ground. It’s what has prevented him from racking up sacks as he’s been in the backfield on numerous occasions. Recently, Bosa told Matt Maiocco that he didn’t “even care that I missed a couple (of sacks) because we got the win and other guys had great games. I’m just glad I did my part.”
“I don’t know what happened on that. I got cold feet,” said Bosa, the No. 2 overall pick in the draft. “It’s coming together. I just got to keep going. The finishing part is tough because you never practice it. Sometimes it’s like, ‘Wait a minute, I beat the lineman, so what do I do now?’ It’s just getting used to finishing plays, and that will come.”
As you can see, Bosa has struggled to stop his powerful rushes that oftentimes end with him on the ground. For a defensive lineman, getting around the edge quickly and then having to stop and hit the quarterback abruptly is not really something they can do each day in practice since teams do not allow their defenders to hit the quarterback. And he took his first live in-game reps against Tampa Bay since deciding to sit out the rest of the 2018 season at Ohio State, just about one full year of time off.
The 49ers expect Bosa to be fully, if not mostly, healed from an ankle injury and that does not bode well for Baker Mayfield, who in their last meeting in college, Bosa recorded a sack and a hit.
Once Bosa unlocks his potential, the sacks will come, and fans need to be patient with this. Yes, he is the number two overall pick and fans want production now. He’s giving it and affecting the game in other ways that some of the more recent first-round picks have not. He’s also not fully 100% healthy after sustaining a preseason ankle injury, and at least some (or most) of the balance issue is being affected by that ankle. Whatever the case may be, I don’t think we’ve seen his full complement of talent just yet.