Two Sundays ago, the Cowboys and Eagles squared off in a game that ultimately decided the division title. While the Cowboys did win the game with a dominating performance in the final third of the game, the frequency of kick-offs from midfield and the lack of aggression by the kicking team seems peculiar. Personal foul penalties by the defense on plays resulting in a touchdown, successful extra point attempts, or dead-ball are enforced on the kick-off. Those fifteen yards lead to the ball being kicked from the fifty yard line. From there, the expected win probability and expected points can be calculated.
Dallas’s WP and EP for an onside kick up 28-24, 0:39 remaining in the 3rd Quarter
After a penalty on Nolan Carroll for unnecessary roughness after a fourth Cowboys’ touchdown, the Cowboys were presented with this scenario. Above is a chart that gives the Win probability and Expected Points probability that Dallas had at the time of the kickoff, according to Brian Burke’s EP and WP calculator. Assuming that the kickoff would be a touchback is conservative as the Harvard Sports Analysis Collective calculated (Note: Jeremy Maclin would return the kick to Philadelphia’s 21-yard line. The HSAC also states that surprise onside kicks were successful 60% of the time from 2001-2010, albeit a small sample size. For an onside kick to be worth it in this situation a team must expect that it would convert about 28% of its surprise onside kick. That is less than half the league rate over that ten year span. Even including expected onside kicks, the success rate of onside kicks is 35%, a difference significant enough to make the risk worthwhile.
The main problem here is convincing a team to put this in action. If Jason Garrett opted to take the onside kick and failed, the media would have thought he was absurd for taking an onside kick with the lead, despite the mathematical evidence to support the reasoning. When Jeff Fisher took a field goal down nine from Arizona’s goal line a few weeks ago, Grantland writer Bill Barnwell made a keen observation on his podcast: many coaches make decisions that delays the inevitably of a loss rather than optimizing their chances of winning. Many coaches choose to make conservative decisions to remain in a closer game for a longer period rather than take a risk that could severely diminish their team’s chances of winning. Regardless, Week 17 will see a lot of desperate teams on the cusp of a playoff berth willing to make bolder decisions. Maybe one will even attempt an onside kick from midfield.