In what could very likely have been a preview of this year’s NFC Championship game, the 49ers scored 48 (48!) points on their way to a last second victory over the Saints. We all know Kyle Shanahan is a tremendous offensive play-caller and designer. And he had his best day of the season in New Orleans.

The 49ers have been one of the best play-action teams in the league this season, and last week was no exception. Jimmy Garoppolo finished 10-13 for 186 yards and 2 touchdowns off of play-action on the afternoon (he started the game 9-9 for 181 yards and 2 TD). The below play is a great example of how Shanahan’s play-action design was able to break down the Saints Defense and create huge voids in the secondary.

This was 1st-and-10, a great time to call play-action. You can see below that the play-fake to the right caused linebacker Craig Robertson to step up in response.

But that wasn’t enough to make this play work. As part of the design, Shanahan had fullback Kyle Juszczyk sneak through the line and run an out to the flat. This held Robertson, preventing him from turning and sprinting to hunt up any receivers at the intermediate level on what was clearly play-action designed to target the zone behind him.

The inside receiver to the right of the formation, Emmanuel Sanders, ran an in-breaking route. His stem took him upfield just enough to make the safety to that side, who was responsible for the #2 inside vertical route, gain depth and start locking onto Sanders. He would end up turning his hips inside to follow the route.

With the underneath linebacker sucked up to the line of scrimmage, and the deep safety occupied by the inside vertical route, the middle was open. Wide receiver Deebo Samuel did an excellent job of widening the outside corner to ensure he had leverage inside. The design of the play created a huge void for Garoppolo to exploit.

The 49ers were in the end zone just two plays later.

Another aspect of Shanahan’s passing game that was effectively on display against the Saints was his use of tight splits, stacks, and bunches.

The use of tight splits enabled San Francisco’s speedy receivers to get free releases off the line, and in many cases, gave them inside leverage to attack the middle of the field.

On this key 3rd-and-5 in the 4th quarter, the 49ers aligned in a tight stack to Garoppolo’s right.

Eli Apple had Deebo Samuel in man coverage. However, due to the stacked formation and the tight split, he was not able to jam or redirect Samuel at the line of scrimmage, which gave him the free release. You can see from the picture below that the tight stack also got Apple to play with outside leverage.

The combination of a free release and inside leverage enabled Samuel to quickly get on Apple and use a speed cut inside to create separation. The result was a big first down that would eventually lead to a touchdown.

With 39 seconds remaining in the 4th quarter and trailing by 1 point, the 49ers faced a 4th-and-2. This was the game. With home-field advantage on the line, Shanahan again utilized tight splits. This time, it was out of a trips bunch formation.

You’ll also notice from the illustration above that the Saints were playing 2-man on this play (man coverage with 2 deep safeties). A benefit of this coverage is that the underneath man defenders can generally feel more confident being aggressive and staying between their receivers and the quarterback, knowing they have help over the top. The tight trips bunch formation negated that, though. As a result, tight end George Kittle was able to get a free release off the line, keeping the timing of the play intact.

Another look from the end zone angle shows you why this play worked. Below you can see how the Saints matched up to the tight-bunch formation.

Kittle’s man, safety Chauncey Gardner-Johnson, had to fight through the release of Kendrick Bourne (#84). Kittle did a great job staying square with his stem, meaning he could have cut to the middle or to the sideline. Even if Gardner-Johnson was able to get a read on the route and wanted to jump the outside, he had to wait for Bourne and his defender to clear upfield first.

The result was the game-defining play. George Kittle is a grown man in case you weren’t sure.

Kyle Shanahan did a great job of putting his team in a position to succeed with scheme all afternoon. Not seen above are the various misdirection plays he used to generate big chunks of yards, including a touchdown pass from wide receiver Emmanuel Sanders to running back Raheem Mostert.

Jimmy Garoppolo also executed well all afternoon, generally making the right reads and accurate throws that gave his receivers the ability to create yards after the catch. This team has a ton of speed on offense, so throwing “runner’s balls” is critical for generating big plays.

To finish the regular season with home-field advantage in the playoffs, the 49ers will have to overcome injuries to Richard Sherman and Dee Ford. This is certainly doable given the fact that they likely have the most balanced overall team in the NFC. If Kyle Shanahan keeps calling games like he did in New Orleans, the road to the Super Bowl will go through San Francisco.

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