To a degree, hockey is a game of luck. There are a lot of players on a slippery surface at the same time, and the puck can take unpredictable paths. Chaos occurs, and teams and players can sometimes benefit or suffer from the randomness. It tends to even out over the course of an 82-game season, but weird things can happen in smaller samples.

However, the NHL season is roughly a quarter of the way done, and that's long enough to start establishing some trends. It's also a short enough window that it's not necessarily a perfect reflection of how good everyone is and what to expect going forward.

At the individual level, there are some players who are experiencing a particularly great run of offensive performance but whose underlying numbers don't necessarily suggest they'll maintain such a high level the rest of the way.

Here are five players whose current point production is unsustainable.

Andrew Mangiapane, Calgary Flames

It took a long time for Andrew Mangiapane to get the respect he deserves. Despite playing brilliantly in junior hockey, he went undrafted in 2014 and only in the sixth round in 2015. At 5'10", he beat the height stereotype and proved himself to be a top-six NHL forward the past two seasons. He's taken that to another level this season with 16 goals in 24 games, and he's now being mentioned in the Team Canada Olympic discussion.

Mangiapane is a very good player, but there's been an overcorrection in how he is perceived. To his credit, he's going to the high traffic areas of the offensive zone and creating a number of mid- and high-percentage scoring chances for himself with deflections and rebounds. As opposed to some others on this list, he is not riding a wave of weak goals allowed by poor goaltending.

Still, his current 26.2 shooting percentage is unsustainable. His previous career shooting rate of 16.2 percent would put him at roughly 10 goals this season. That would still make him a major contributor, but with Mangiapane currently tied for third in the NHL in goals, he is a paper tiger in the Rocket Richard Trophy race and should drop down that list as the season progresses.

Ryan Hartman, Minnesota Wild

It's funny how much shooting variance can affect the narratives surrounding players. Kevin Fiala has become a lightning rod for trade speculation in Minnesota for many reasons, one of which is his abysmal 3.8 shooting percentage.

For now at least, he's fallen behind fellow Minnesota Wild winger Ryan Hartman on the depth chart, and Hartman is getting all the luck that Fiala isn't. He scored 19 goals in his rookie 2016-17 season and then hadn't breached the 10-goal mark until this season in which he's inexplicably found the net 13 times through 23 games.

Good for him to start the season so well, but the goal-scoring numbers don't tell an accurate story. For starters, two were empty-netters. Beyond that, he's benefitted from less-than-stellar goaltending. Over a third of the remaining 11 goals came from Hartman shooting low-percentage shots from the perimeter on rushes. His overtime winner against Anaheim is a great example.