Chip's Challenging Decisions

The Eagles lost to the 49ers on Sunday 26-21 in what essentially came down to two plays by the Eagles on 3rd and 4th-and-Goal from just outside the 1-yard line. There is no denying it was a close game - even though the Eagles offense was unable to move the ball all day. The Eagles made a few interesting decisions - or lack of decisions - in the second half including not challenging a 3rd-down conversion reception and accepting a penalty on 3rd-and-3 after an incompletion. Let's examine each and see how they could have affected the Eagles' win probability, keeping in mind that in close games, every percentage point counts.

Throw The Red Flag

With 2:09 left in the 3rd quarter, winning 23-21, San Francisco faced a 3rd-and-9 from their own 27. Colin Kaepernick dropped back and hooked up with Anquan Boldin for a 12-yard completion. It appeared Boldin bobbled the ball and potentially trapped it on the completion. In today's game where most of the biggest plays are automatically reviewed (scoring plays and turnovers), a long 3rd-down conversion in a close game is one of the higher leverage challenge situations.

Lambeau Madness & Twitter Outcries

With a little over five minutes remaining in the 3rd quarter, down 17-14 to the Steelers, the Packers had their field goal blocked only to have chaos unleashed at Lambeau. I won't go into the details, but essentially it was ruled that the Steelers never had full possession (when they did and should have been determined down by contact) and then due to an illegal batting out of bounds, the Packers got the ball back with a fresh set of downs, 1st-and-Goal from the 2-yard line.

All holy heck has broken loose in Green Bay.
— Rich Eisen (@richeisen) December 22, 2013

Twitter erupted. Everyone was outraged at the blasphemous call. And even more, everyone was outraged that possession was an unchallengeable call. All over the place, people were comparing it to the Seattle/Green Bay replacement ref debacle from last season.

When the Defense Should Decline a Penalty After a Loss Part 2 (2nd Downs)

I recently looked at when it made sense for the defense to decline a 10-yard holding penalty following a 1st down play for no gain or a loss. It turned out that defenses should generally prefer to decline after a loss of 3 or more yards.

First downs are easier to analyze because they almost always begin with 10 yards to go. Unfortunately, 2nd downs aren't so cooperative. It's amazing how thin he data gets sliced up. Most downs aren't losses, even fewer have holding penalties, and rarely are they declined. Still, there are enough cases for a solid analysis using 1st-down conversion probability as the bottom line.

Put simply, a defense would prefer to decline a penalty on a 2nd down play whenever the resulting 3rd down situation leads to a conversion less often than the 2nd down plus the 10 yards.

The chart below plots conversion probability for 2nd and 3rd down situations. The red line illustrates the conversion probability of 3rd down and X to go situations. For example, 3rd down and 7 situations are converted about 40% of the time.

The green line illustrates 2nd down situations, but slightly differently. It plots conversion probabilities for 2nd down and X plus 10 yards. For example, 2nd and 13 (i.e. 3 + 10 yds) situations are converted 45% of the the time. The black line is the smoothed line fitted to the 3rd down conversion rates. I plotted things this way because it's the actual comparison we're interested in, given a gain of zero yards.

When Should the Defense Decline a Penalty After a Loss? Part 1

Let's say there's a sack or other tackle that results in a several-yard loss. And to compound the offense's woes a flag for holding is thrown, potentially setting up a 1st and 20 situation. Should the defense accept or decline the penalty and force a 2nd and X? We can evaluate this question in a few ways. We'll use a simple method and a more complex method to find out when a defense should normally decline a penalty on first down.

Before you read on, what do you think the break-even yardage is? What do you think most coaches think it is?