Analyzing Kyle Shanahan’s Super Bowl OT decisions

Kyle Shanahan’s decision to receive the football has been universally roasted

“They’re crazy. They’re crazy.”

Kansas City Chiefs defensive tackle Chris Jones had this to say about San Francisco 49ers coach Kyle Shanahan’s pivotal decision in the Super Bowl.

With the game tied at 19 and heading to overtime, Shanahan chose to take the ball after the 49ers won the coin toss. In so doing, many analysts believe he sealed San Francisco’s fate — another championship defeat at the hands of Patrick Mahomes.

Was it a mistake, though? How do the playoff-specific rules change the calculus of receiving or defending the football?

New playoff rules

In one of the most epic games in NFL history, the Chiefs defeated the Buffalo Bills, 42-36, in the 2021 AFC Divisional Round. After tying the game on a field goal following a 13-second drive, the Chiefs won the coin toss in overtime and drove down for a game-winning touchdown. Josh Allen never touched the ball in overtime after delivering a monster performance in regulation.

After a general public uproar, the NFL Competition Committee changed the overtime rule for the playoffs only. Each team would be given at least one possession regardless of whether the first possessing team scored a touchdown. The only way the game could end after one possession was with a defensive score.

When these rules were implemented, a flurry of analytical discussions ensued. Should the team winning the coin toss take the ball or defer? What about going for two? How do fourth-down decisions work?

This Super Bowl was the first time we actually saw the new rule in practice, and of course, Shanahan’s decision is now mired in controversy.

They didn’t know

Shockingly, multiple 49ers players expressed after the game that they did not know the rules were different in the playoffs.

According to The Ringer’s Lindsay Jones, “Multiple San Francisco players said after the game that they were not aware that the overtime rules are different in the playoffs than they are in the regular season, and strategy discussions over how to handle the overtime period did not occur as a team.” Jones explained that defensive tackle Arik Armstead learned the rules from the video board, while fullback Kyle Juszczyk assumed the rules and strategy were the same as during the regular season.

Meanwhile, the Chiefs had practiced all the scenarios in the two weeks before the game. They were aware of the rule change going back to training camp.

Did that ultimately make a difference? Likely not, because Shanahan knew the rules and the permutations. Still, it could have affected players’ in-play decision-making.

This scenario is reminiscent of Donovan McNabb’s infamous lack of awareness that an NFL game could end in a tie back in 2008. His head coach then? Andy Reid.

Receive or defer?

While Shanahan is facing heavy criticism for his decision to receive the ball in overtime, it is not entirely fair.

From an NFL analytics staffer this morning on first vs. second possession in playoff OT:

"Anyone that is very confident there is a clear option is probably wrong."

— Seth Walder (@SethWalder) February 12, 2024

Doing a quick poll of analytics staffers on what they would have done if they were 49ers last night in playoff OT. Seven votes in so far:

1. Strongly prefer first possession (0 votes)

2. Lean first possession (2 votes)

3. Almost 50-50 (3 votes)

4. Lean second possession (0…

— Seth Walder (@SethWalder) February 12, 2024

Here was Shanahan’s explanation for his decision after the game.

“It’s just something we talked about. None of us have a ton of experience with it, but we went through all the analytics and talked to those guys — we wanted the ball third. If both teams matched and scored, we wanted to be the ones who had the chance to go win. We got that field goal, so we knew we had to hold them at least to a field goal, and if we did, then we thought it was in our hands after that.”

Considering how the 49ers’ pass rush had played for much of the night, it wasn’t an unreasonable thought process. Kansas City had gone 1-for-4 in the red zone to that point with one touchdown, two field goals, and one lost fumble. Shanahan felt that his defense could hold the Chiefs in check and give his team the chance to win on a field goal.

Even in a generic situation, that logic isn’t unsound. After those first two possessions, if the game remains tied, it reverts to sudden death overtime. In that case, the 49ers would have possession and the first chance to win the game.

Here are the flaws with that reasoning, though.

Fourth down

The most basic reason to defer the coin toss is that the second team to possess has an automatic extra down. If the first team scores on their opening drive, the next team will automatically go for it on fourth down, at least until they’re in field goal range.

That’s exactly what happened when Kansas City was forced to go for it on fourth-and-one from their own 34. Had they been the first team to possess the ball, they would have almost certainly punted (regardless of whether that was the correct analytical decision).

Reaction

On a more basic level, the second team to possess the football knows what they’re dealing with.

• The first team didn’t score? A field goal wins the game.
• The first team scored a field goal? A field goal ties, a touchdown wins.
• The first team scored a touchdown? Score a touchdown and go for two to win.
• The first team scored a touchdown and went for two? A touchdown and two is necessary.

The ability to react to what the first team did is valuable strategy-wise. The Chiefs knew that a) they needed to go for it on fourth down and b) they needed about 35-40 yards to set up a game-tying field goal. That’s very different than the approach with the first possession.

It’s worth noting that the regular college overtime rules mirror these NFL playoff overtime rules. In college, teams almost always defer when they win the coin toss for these exact reasons.

Furthermore, the NFL includes this calculus in their explanation for the rule changes — both the reasons to defer and Shanahan’s reasoning about getting the ball third.

Expected points

From an analytical perspective, the 49ers started their drive with 1.21 expected points, while the Chiefs began theirs at 1.38 (per RBSDM). This likely takes into account the difference in fourth-down decision-making, as both teams began from the same point on the field (their own 25).

Still, a difference of 0.17 EP is not exactly dramatic.

Kick or go?

The bigger mistake Shanahan made was perpetuating the disadvantage of getting the ball first.

On their overtime drive, San Francisco methodically drove the ball down the field before stalling at Kansas City’s nine-yard line. They faced a fourth-and-four from there. Shanahan chose to send out the field goal unit.

The win probability was very similar: per ESPN Analytics, it was a 75.4% probability if they went for it and 74.5% if they kicked. Still, 0.9% is a big difference when the quarterback on the other end is Patrick Mahomes and the play-caller is Andy Reid.

Interestingly, earlier in the game, Shanahan was extremely aggressive in going for it. He could have taken Dan Campbell criticism if the 49ers had failed. They faced a fourth-and-three from Kansas City’s 15, down 13-10. Shanahan chose to go for it rather than tie the game with a field goal. It worked, and San Francisco scored a touchdown to take the lead.

A Kyle Shanahan game management W!!!!! pic.twitter.com/K6g450AOgN

— Seth Walder (@SethWalder) February 12, 2024

Alas, a low extra-point kick led to a block, which was far more decisive in the game than anything Shanahan did.

Still, when it mattered most, Shanahan chose to be conservative. In doing so, he gave Kansas City the advantage that the first possessing team has in overtime during the regular season — the opportunity to score a touchdown and end the game before the other team possesses the football.

What if…

The fascinating “what if?” that will never be answered is what Shanahan would have done if the 49ers scored a touchdown.

Would he have gone for two to try to guarantee himself that third possession, which was the backbone of his rationale for receiving the kick?

The Chiefs already stated that had the 49ers scored a touchdown, their strategy would have been to score a touchdown and go for two to win the game. But what if Shanahan had forestalled that possibility with his own two-point conversion?

This was a big part of strategy discussions when the new playoff overtime rule was first implemented. The second team would undoubtedly choose to go for two based on the analytics showing that going for two has a higher win probability than tying the game with an extra point. Would the first possessing team then also go for two to negate the possibility of losing on a two-point conversion?

Alas, we will never know the answer (unless someone asks Shanahan the hypothetical question), as Shanahan chose the conservative way out. Perhaps he will rue the decision to kick that field goal more than the choice to take the ball in overtime.