The Winnipeg Jets last season prided themselves on smart, effective defense.

This season has been a bit different. Both by the eye-test and numbers, the Jets have not been nearly as effective in preventing opposition chances.

How worried should we be?

The Jets haven’t been great defensively. It’s been pretty obvious with the eye-test, but the numbers show it too.

The Jets have actually been better than league average in preventing shot attempts, but worse than average in unblocked shot attempts, shots on goal, scoring chances, and high-danger scoring chances.

It’s an odd thing to see, since the Jets were above average the previous season.

We can look at the Jets performance using WAR-on-Ice‘s scoring chance metric and compare the Jets this year to last season.

We can see here that the Jets were pretty decent in the prevention chances against, and also in creating chances for over the 2014-2015 season. The same cannot be said for this season though.

The season is early though. Most teams have played 5-7 games, which is not exactly a significant sample to draw from. Teams vary greatly in the type of competition they have faced, travel schedule, rest days, and other factors.

There is also the human factor. Hockey players are not machines that put out consistent effort to the maximum of their abilities day-in-and-day-out. Skaters have hot streaks and slumps. At six games, a combination of players slumping or opposition playing beyond their norm can skew the numbers.

This is why we find that even the best shot metrics carry low predictive value, in both predicting themselves (graphical example: Corsi predicting Corsi) and future success (graphical example: Corsi predicting goal differentials).

There are some legitimate concerns though with the Jets consistency in being out chanced.

The only games where the Jets allowed less than average number of events against was against the New Jersey Devils, a middling-to-bad team that plays an extremely low event game, and the Calgary Flames, a team well known for giving a bevy of high-quality chances against.

Otherwise, the Jets’ defensive performance leaves a lot to be desired.

The season is still young. The sample size is not overly significant, there is time for Paul Maurice to make adjustments with the Jets’ system and roster, and there is the ebbs and flows of human performance.

There are some concerns, but it’s a bit early to to be crying that the sky is falling.