Two of the most clutch QBs of 2010 face off tonight as the Falcons host the Saints. Although 'clutch' performance may not be a persistent skill in players, there undoubtedly exists clutch play itself. Due to the varying leverage created by the combination of score and time, some players will have their better moments when they matter most, and some players will have their worst moments at just the wrong time.
Here's one way to measure which QBs are most 'clutch' this season. WPA accounts for the leverage of score and time while EPA ignores it. We can plot each QB's Win Probability Added (WPA) against his Expected Points Added (EPA), creating a baseline expected WPA for each QB.
Next, we can measure the difference between each QB's expected WPA and his actual WPA. This difference could be considered clutch-ness. This is illustrated in the graph below. The vertical red line happens to be the clutch-ness of the most clutch QB of 2010, Matt Ryan.
The table below lists the QBs from most clutch to least so, according to their differences between actual WPA and expected WPA. Matt Ryan's has over-performed his expected WPA by about 2 full wins. We could say that the guys at the top of the list are playing over their heads to some degree, while the guys at the bottom of the list have been snake-bitten. I would expect to see some regression-to-the-mean effects at some point for guys like Ryan and Flacco, and I think we've already seen Sanchez's play fall back down to Earth in recent weeks.
The guys in the middle of the list have posted WPA numbers about what we'd expect given their EPA numbers. That doesn't mean they're poor clutch performers at all. It just says that they perform about equally well in the clutch as they do in most other situations.
A logical next step would be to measure the consistency of clutch play, to begin to probe the question of whether there is anything to the notion that it's a persistent skill or something else. With the small sample sizes and large variance in outcomes, I doubt it's measurable even if it exists.
Note: Stats are through Sunday's (12/26) games.