Week 15 Fantasy Football: Thursday Night Football analysis for San Francisco 49ers vs. Seattle Seahawks

I’ll be honest. I’m not ready for tonight. The injuries and storylines from Week 14 still have me reeling. Practice reports and beat-writer tweets have never played a larger role than they do in the first week of the fantasy playoffs. But we’ve got a game tonight! A divisional rematch with playoff implications, no less.

With multiple high-end fantasy stars on both sides, let’s dig into the battle of the NFC West between the San Francisco 49ers and Seattle Seahawks.

Divisional rematch on TNF: Seattle … the unexpected playoff team

It was fair to expect a positive jolt to the 49ers offense after Jimmy Garoppolo’s injury. We’ve seen the Nick Mullens and C.J. Beathards of the world pop up for good games in relief. But I had doubts about a seventh-round rookie going against a Todd Bowles defense.

Brock Purdy put those concerns to rest right away:

As I expected, Tampa sent most of their defense after the inexperienced passer. They pressured Purdy on 40.9 percent of his dropbacks. And he lit them up for 109 yards and two scores. His 158.3 passer rating against pressure is the only time a quarterback saw an above-average pressure rate (34.8%) with a perfect score.

But, of course, his play gets amplified by the guys around him.

[Watch Thursday Night Football on Prime Video: Sign up for a 30-day free trial]

Deebo Samuel is out, but the rest of the crew is ready to roll. Christian McCaffrey continues to put defenses in a bind as both a runner and a receiver. He’s 10th in explosive runs and 24th in YPRR amongst all pass-catchers. Meanwhile, Brandon Aiyuk is top 20 in YPRR independent of the coverage scheme (20th against man, 18th against zone). And, of course, there’s George Kittle, who has more YAC per reception (6.1) than Jaylen Waddle (5.9) and Tyreek Hill (4.7).

I’ll have some notes on an ancillary player behind this trio shortly. But even with Purdy’s possible physical limitations, the 49ers should have no trouble moving the ball.

On the other side, I expect Seattle to struggle, but they’ll keep the game close with Geno Smith.

The Seahawks are 3.5-point home underdogs, which makes sense given both teams' recent performances. Plus, the “underdog” moniker kind of fits this team. Nobody expected Seattle to be here back in August. The Seahawks are playing with house money but still have a shot at winning this game.

Seattle's struggles aside, the offense is still sixth in EPA per play. It's dropped to 11th after their bye, but they’re still averaging 28.3 PPG. Smith's had time to reflect (and hopefully, game-plan) after the first meeting. However, the Seahawks' defense needs a bit more than reflection to keep the team from another shootout.

Seahawks Pass Defense by Game fantasy analysis. (Data by nflfastR)
Seahawks Pass Defense by Game fantasy analysis. (Data by nflfastR)

Seattle had the worst defense per most metrics through the season's first month. They had a positive stretch during the middle of the season, but things have reverted. John Wolford is the only quarterback without at least one passing touchdown against the Seahawks since Week 9. Seattle has given up the third-most yards per game since their bye.

I’ve got more on Geno, but his resurrection has been Seattle’s salvation. The Seahawks have been able to evaluate their younger talent while still playing relevant football in December. Kenneth Walker III can spark the running game with Tyler Lockett and DK Metcalf fighting through traffic downfield.

Smith's response under pressure will dictate the outcome of this game, but I’ve got some questions about San Francisco’s new quarterback, too.

Points of Interest in TNF

Is Purdy really a Shanahan man?

Purdy put on a show in his debut, there's no doubt about it. But stylistically, Mr. Irrelevant operated differently than his predecessors, which is, well, relevant to how we should view him moving forward. His out-of-structure behavior caught my eye first:

Garoppolo falls into the “robot” category when describing quarterbacks. He gets the play from Shanahan, relays it to the team and executes. Justin Herbert falls into the same bucket, but unlike Herbert, Garoppolo doesn’t have the arm strength or mobility to escape defenders.

Purdy showed us he’s willing to put it all out on the field.

Garoppolo only has three scrambles since taking over for Trey Lance in Week 2. Attempts downfield have been more likely for Garoppolo, and they’ve been a mixed bag. He’s 17th in EPA per attempt under pressure. Purdy's only credited scramble (a penalty negated the replay above) resulted in a first down, but his willingness to use his legs can keep the 49ers moving despite Samuel’s absence.

Purdy’s aggression was also noteworthy:

Brock Purdy/Jimmy Garoppolo pass charts. (Photo by NextGenStats)
Brock Purdy/Jimmy Garoppolo pass charts. (Photo by NextGenStats)

We think of the Shanahan offense as a “YAC-enabling” scheme. Samuel and Kittle were top 15 in YAC last season, and the middle-of-the-field targets gave them the runway to create. Garoppolo kept his focus between the numbers (62.2% of his attempts), while Purdy found success on the outside (41.4%). But it might not matter against Seattle.

Regardless, I’m interested to see if Shanahan tweaks the play calls to take more off Purdy’s plate. San Francisco should be able to get out of Thursday night with a win. But with the playoffs ahead, there may be a focus on getting its passer ready for the tough defenses they’re bound to face.

Geno Smith: The eye of the storm

I'm trying to square my preseason thoughts about Seattle with what we've seen, and I can't do it. I can understand why fans and fantasy managers are disappointed, but (I hope) we can all agree Seattle being in playoff contention this season wasn't on our bingo cards. Regardless, it still has been frustrating to watch at times:

Things started to change after their loss to the Buccaneers in Week 10. Before going overseas, Smith had four interceptions and two lost fumbles on the season. He's had the same number of turnovers since Week 12. To be fair, one pick was on an assumed free play, but the setbacks feel like the offense is on a downward spiral. And yet, Geno's kept his cool and still played like one of the better quarterbacks in the league.

Geno Smith QB stats. (Photo by Chris Allen/Yahoo Sports)
Geno Smith QB stats. (Photo by Chris Allen/Yahoo Sports)

Despite the tough losses over the last three weeks, Smith is still top 12 across major passing metrics. The accuracy and efficiency are still there. Seattle's 35.2 yards per drive in those games would still rank top-10. Seattle's defense worries me, and I can't calculate resiliency, but the offense is still productive with Geno under center. Either way, tonight will be their toughest challenge.

Smith’s response to San Francisco’s defense will be telling. Everyone will point back to Week 2 as an indicator of how bleak things are for the Seahawks. But we thought Smith was just a flash in the pan after Week 1. With his development and the offense responding to his command, Smith’s calm (but efficient) approach to the game may be what saves the Seahawks' season.

One Up, One Down: A sleeper to consider and a star to fade

I’m combining two sections this week to make my final thoughts more actionable. Usually, I’d just hunt for players with FLEX appeal and cape up for them. But it's the first week of the playoffs, and we've got tough start and sit decisions ahead of us.

So, I'll start with a player with flex appeal and then dive into another you may need to avoid.

Jauan Jennings

It's easy to assume the targets will be spread around, with McCaffrey, Kittle and Aiyuk being the primary beneficiaries. So Jauan Jennings' prospects as the WR4 are viable for a single-slate DFS contest, given the uncertainty around his usage. But the lack of floor makes him a mid-tier FLEX option for season-long matchups. Regardless, Jennings should see a bump in snaps without Samuel on the field.

Since McCaffrey joined the team, Jennings has been fifth in targets with a 12.2% share. Ray-Ray McCloud may get some love from the boxscore crowd. But McCloud didn't earn a touch until after San Francisco had a three-score lead. Jennings has the highest slot rate (60%) of the ancillary options, with a chance to capitalize on the available targets.

Kenneth Walker III

You’ve likely seen the adage, “Start your studs,” repeated throughout the day. And Walker qualifies as a stud. But not in the traditional sense.

Walker had a 27.6% share of Seattle's backfield touches until Rashaad Penny’s injury in Week 5. When Penny went down, the rookie had a 45.0% roster rate, making him a potential waiver-wire add. But since the backfield switch, Walker's 65.7% of his team's carries ranks seventh in the league, and he scored more times on the ground than Josh Jacobs.

However, this isn’t the matchup to expect many fantasy points from a rusher.

Over Expected % versus Rushing Yards Over Expected. (Data provided by NextGenStats)
Over Expected % versus Rushing Yards Over Expected. (Data provided by NextGenStats)

Walker is 38th out of 39 qualifying running backs in success rate. But he's tied for seventh in explosive runs, which is why he's more of a boom-or-bust player. And there's no other defense with a better ability to limit those types of runs than the 49ers.

Over the last six weeks, San Francisco has allowed five runs over 10 yards. The 49ers have surrendered 18 total this season. Plus, they're third in rushing EPA per play, limiting down-to-down consistency. No rusher has topped 60 yards on them. The last two to find the paint were James Conner (Week 11) and Clyde Edwards-Helaire (Week 7).

With Walker just coming off an injury, I'd look elsewhere for a star performance at running back in Week 15.

Listen to the Yahoo Fantasy Football Forecast

This article contains affiliate links; if you click such a link and make a purchase, we may earn a commission.