�ݺ�ߣ

Greg Ackerman
NFL Punt Analytics Competition

 NFL Concussion Data Set contains
37 punt plays in 2016 and 2017
resulting in a concussion
 To my surprise, 18 concussions
occurred on blocks
 How does the NFL prevent
concussions on blocking plays?

 Punting team formation straight
forward – usually 2 gunners, 5 men
on line of scrimmage
 Return team – biggest difference
between plays is “jammers” (VR, VL)
 With more jammers, the better
protection exists for the returner
 Example: the right gunner in this
play is guarded by two jammers
 More space for returner

Jammers 2016 and 2017 Punts
0 58 (1.2%)
1 47 (0.9%)
2 2,272 (45.6%)
3 1,466 (29%)
4 1,132 (22.7%)
5 3 (0%)
 46% of 2016 and 2017 punts featured
two jammers by the punting team
 3 and 4 jammer plays were less
frequent
 How does this relate to concussions?

 Of the 37 concussion plays, the
number of plays were similar
between the 2,3, and 4 jammers
 2 jammer sets are most frequent
 Only 0.6% of plays with 2 jammers
had concussions
 0.8% with 3 jammers, 1% with 4
 With fewer blockers on gunners, why
fewer concussions?
 Fair catches

 4/18 concussion plays come on plays
with 2 jammers
 The most frequent jammer formation
has the fewest concussions on blocks
 Random variation, or some
substance here?

 Difficult to identify blocks in NGS –
no “Event”, so quantifying collision
forces is incomplete.
 Use median speed of a player during
a play
 Boxplots show the injuring player on
plays with 2 jammers have lower
speed (mph) than plays with 3 or 4
jammers
 Low impact collisions, foul play type of
fouls rather than pancake blocks

Minimizing NFL Concussions on Punt Blocks

 From video, we see muffed punt with
a heavy hit from gunner
 From video, we see muffed punt with
a heavy hit from gunner
 Helmet-to-helmet collision

 Jammers have the gunners
locked up, still lots of pressure on
punt returner
 Blockers must compensate with a
heavy hit
 Blocker leads with his helmet
and a concussion occurs

 Illegal blindside hit before punt even
reaches returner (punt was downed)
 Blocker tried to nudge a pad, got the
kicking team player’s head
 Lower-impact hit than the 4 jammer
hit
 The problem was not that there were
two jammers on this play

 Punt formation:
 The kicking team is allowed at most
two gunners lined up outside the yard-
line number on punt, and must have
an equal number of gunners on each
side.
 The return team may have no more
than two jammers on a play, and a
jammer must be aligned with a
gunner.
 Penalty: 5-yard illegal formation
based on offending team

The Rule
 Punt formation:
 The kicking team is allowed at most
two gunners lined up outside the yard-
line number on punt, and must have
an equal number of gunners on each
side.
 The return team may have no more
than two jammers on a play, and a
jammer must be aligned with a
gunner.
 Penalty: 5-yard illegal formation
based on offending team
Why it works
 Lowest frequency of blocking
concussions on punt play ”jammer”
formations
 Increases fair catches, in which case
blocks are limited to the kick’s
hangtime

 The proposed rule already enforces a legal formation, of which was used on 46% of
2016 and 2017 punts
 Safety concern: Punt Returner being susceptible for heavier hits
 Fair catch baked into rule book, protects returner from these hits
 For consideration:
 Impact on punt return touchdowns, fair catches, and penalties

Jammers Count Touchdowns
Touchdown
Frequency
Fair Catches
Fair Catch
Percentage
Penalties
Penalty
Frequency
2 2,271 18 0.793% 1,099 48.4% 457 20.1%
3 1,466 21 1.43% 348 23.7% 341 23.3%
4 1,132 13 1.15% 192 17.0% 308 27.2%

Jammers Count Touchdowns
Touchdown
Frequency
2 2,271 18 0.793%
3 1,466 21 1.43%
4 1,132 13 1.15%
 Touchdowns are rather infrequent, but
still a part of why punt returns exist
 Touchdown frequency on 2 jammer
formations is lower than that with
greater
 (Naïvely) assume true TD% on 2
jammer punts is 0.793%, and rule is
enforced
 .0793% * 4,689 punts = 39 touchdowns
 Actually 52 touchdowns in 2016 and
2017
 Hypothetical 13 touchdown drop across
two seasons

Jammers Count Fair Catches
Fair Catch
Percentage
2 2,271 1,099 48.4%
3 1,466 348 23.7%
4 1,132 192 17.0%
 Drastic difference on fair catches
based on number of jammers
 Fair catch percentage for 2 jammer
formations is a very high 48.4%
 Major safety concern: since punt
returns would be more infrequent,
punt returners may act sub-optimally
and not call fair catch on plays they
would have under previous rules
 Punt returner more susceptible to
concussions and injuries on a heavy hit
 Fair catch rate drops below 48.4%

Jammers Count Penalties
Penalty
Frequency
2 2,271 457 20.1%
3 1,466 341 23.3%
4 1,132 308 27.2%
 Fewer Jammers = Fewer returns =
Fewer penalties
 Using a similar naïve approach to
earlier:
 20.1% * 4,869 punts = 976 penalties
 Actual: 1,106 penalties
 1,106 – 976 = 127 hypothetical penalty
decrease
* While this rule cuts down on the
excitement of 13 touchdowns over 2
seasons, it also prevents 127 penalties.

Solution Efficacy
 Limits concussions on blocking plays,
which are about as common as
concussions on tackling plays
 Keeps punts in football
 Doesn’t re-invent the wheel – a
casual fan might not even notice the
difference
 A special teams coordinator definitely
would, though
 Decreases number of penalties
 Speeds up the game, though may not
add up to very much time saved in the
end
Football Considerations
 Negative entertainment value
 Fewer returns
 Fewer touchdowns
 Doesn’t fully ”tackle” concussions on
tackles on punts
 Returners may return punts in
higher danger than in previous to
adjust to the rules

 If this rule prevented even one concussion, it can prevent CTE or lifelong head
trauma for an athlete. While the football considerations are quite real NFL
football operations decisions, sacrificing 6-7 punt return touchdowns a season and
seeing more fair catches would be worth it if a life is saved.

�ݺ�ߣ

Minimizing NFL Concussions on Punt Blocks

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