Brian Burke of
Advanced NFL Stats sent us an e-mail on the Steelers’ unorthodox decision
to try an onside kick in their victory over the Packers. He gave us permission to re-run
his blog post, and here it is:
Up by 2 points with 3:58 left against the Packers, Steelers Coach Mike Tomlin called for an onside kick. Was it a good decision?
When onside kicks are expected, they are successful only about 20% of the time. But unexpected onside kicks are successful a surprising 60% of the time. I think we can say this particular kick was certainly unexpected. And surprise onside kicks can be most beneficial when a team is ahead late in the game. Possession is critical.
In this case, had the Steelers recovered the kick, they would have had a first down at about their 40, which is good for about a 0.76 win probability (WP). An unsuccessful onside kick gives the ball to the Packers at the Steelers’ 40, worth 0.58 WP for the Packers (which is 0.42 WP for the Steelers.) With a 60% success rate, the overall WP for the onside kick would be:
0.60 * 0.76 + (1-0.60) * 0.42 = 0.64 WP
A conventional kickoff gives the Packers a 1st and 10 at their own 30 or so (28 is the average, 33 is the median). This gives the Packers a 0.46 WP, which is 0.54 WP for the Steelers.
The onside kick is the better decision by 0.64 to 0.54 WP. These estimates are only league baselines, but they suggest it was probably a good call. What’s most interesting to me is that a failed onside kick is hardly certain death — a 0.42 WP. There was plenty of time for anything to happen — a stop, a turnover, a score. And sure enough the Steelers gave up a touchdown but came back with one of their own.
Also, a successful onside recovery doesn’t seal the game. The Steelers would still need at least two first downs to clinch the win. Essentially, the Steelers traded 30 yards of field position for the chance to keep the ball out of the Packers’ hands.
Tomlin has HUGE BALLS???
so in a high scoring game, coaches should just onside kick all the time?
