Whose slump is a sign of a permanent decline?

"Don't panic."

That phrase once appeared on the cover of a famous book. And it should probably appear on the cover of programs in NHL arenas, because it's good advice for hockey fans who like to overreact to slow starts and small sample sizes. Most of the time, an early-season slump is just a slump, and the right response is to shrug it off and move on.

And yet, sometimes a slump is more than that. Sometimes it's the start of something bigger, the sort of long-term downturn that changes the way we view a player. A seemingly minor slump might end up being that first blinking light on the dashboard, warning us that a player could struggle through the rest of the season or even career.

The problem, of course, is that we don't really know when that's the case; we have to wait and see how it all plays out. But that doesn't mean we can't carefully analyze the situation in an attempt to figure it out and then take a wild guess. So today, let's look at eight names from around the NHL world who are off to a rough start and try to answer the question: Is it time to panic?

Jakub Voracek, Philadelphia Flyers

The season so far: One year after enjoying a breakout season (and signing a $66 million extension), Voracek has no goals. That's bad, right? I think that's bad.

Panic time? You could forgive Flyers fans for being nervous here -- after all, no franchise has a longer track record of seeing big-money contracts blow up in its face. And Voracek's lack of goals isn't exactly a new development. Even during last season's breakout, he had only six goals in the second half. And while he's never been a pure goal scorer, even his five assists on the season are well below expectations. All that said, a look beyond Voracek's boxcar stats shows some positive signs. He leads the team in shots on goal by a wide margin, and his possession numbers are as strong as ever. Voracek himself sounds as though he's getting frustrated, and guys carrying cap hits north of $8 million don't often get much benefit of the doubt. But Voracek deserves at least a little bit of patience here because his numbers say he should get on track soon. So don't throw any batteries at him, Flyers fans. Or at least no more than usual.

Ryan Getzlaf, Anaheim Ducks

The season so far: I'm not saying it's been a tough season for the Ducks, but we also would have accepted Corey Perry, Jakob Silfverberg and Ryan Kesler. And also pretty much everyone who plays for Anaheim and isn't a goalie.

But Getzlaf gets the nod, based on a season-long goalless slump. Granted he missed a few games for an appendectomy. But he's just looked off at times, and doing stuff like this doesn't help.

Panic time? Getzlaf is on the wrong side of 30, so anything approaching a long-term slump is cause for concern -- age comes for everyone eventually, and when it does, the downturn can often be sharp and brutal. But this slump hasn't quite hit "long-term" status yet, and Getzlaf has looked good playing with Perry in recent games. The Ducks are slowly but surely shaking off their awful start, and since they're in the Pacific, they haven't exactly been left behind by the rest of the division. They should be OK, and their captain should too.

Nick Foligno, Columbus Blue Jackets

The season so far: There are plenty of other Blue Jackets to choose from -- Sergei Bobrovsky being a prime candidate -- but with a big new contract kicking in this season, the captain gets extra attention. The results so far: just one goal in 16 games. And now his new coach is singling him out.

Panic time? In his first six seasons in the league, Foligno had a shooting percentage of just more than 10 percent, which is above average. In his past two, that number jumped to almost 17 percent. That indicated one of two things: Foligno was one of the rare players who saw a big leap in his offensive abilities after his 25th birthday or that his breakthrough numbers were getting a boost from some unsustainable good luck. Analytics fans know which answer is most likely, and it's not the one Blue Jackets fans will want to hear, especially after seeing the team lock Foligno up with a six-year, $33 million extension. That deal looked like a classic overreaction to a big contract year, and the reality is that Foligno almost certainly isn't the consistent 30-goal scorer the team seemed to think it was buying.

Of course, he's still is a solid two-way player who can find ways to contribute even when he's not scoring. And shooting percentage cuts both ways: Foligno's current 2.4 percent screams of a player who should start getting some bounces soon.

So panic? That's probably not the right word here. Foligno should get back to normal soon. But his normal isn't what we saw last season, despite what his contract might tell you.

Tuukka Rask, Boston Bruins

The season so far: Rask has had an up-and-down season. He's currently 4-5-1 with a .891 save percentage that ranks 37th among the 42 goalies with at least five starts. He's already given up five or more goals in four starts, after having just three such games all of last season. He's getting (mildy) called out by president Cam Neely, and he was passed over for the start in Saturday's big rivalry game in Montreal.

Panic time? Rask has a solid body of work to his name, ranging from very good to downright excellent in his six full seasons before this one. And he's not exactly in danger of losing his job; the Bruins' other goalie is Jonas Gustavsson, and when your resume includes "Not good enough to be a backup for the Toronto Maple Leafs," you're probably not scaring too many Vezina winners.

So no, it's not panic time here, and Sunday's strong game against the New York Islanders was a good sign. But given that the middling Bruins don't figure to have much margin for error this season, there's a sense of urgency for Rask to get back on track. Plenty of experts picked the Bruins to miss the playoffs this season, but after disappointing starts for every Atlantic team that isn't Montreal, the road to the postseason is wide-open. The Bruins have as good a shot as anyone right now but only if the old Rask shows up sooner than later.

Patrick Roy, Colorado Avalanche

The season so far: Hey, nobody said we had to limit this list to players. And while Roy isn't the only coach having a rough season -- Bob Hartley (Calgary) and Bruce Boudreau (Anaheim), say hello -- the 2014 Jack Adams winner's 5-9-1 start has some wondering whether he's on the hot seat.

Panic time? Yep. And maybe we should have already been there a long time ago. Many Colorado fans have been.

Roy's rookie year behind the bench saw the Avalanche make an unexpected surge to first place in the division. That earned him the Jack Adams and enough benefit of the doubt that many were willing to forgive last season's disappointing drop to 90 points and last place in the Central.

But after watching the Avs stumble through the season's first month -- all but falling out of playoff contention while putting up their usual putrid possession numbers -- it's getting hard to ignore the possibility that Roy just isn't a great NHL coach. Or, at the very least, that he's not the right guy for this Avalanche team. He's faced plenty of criticism for his lineup decisions, and his "we're not so bad" pep talks are starting to wear thin. It's hard to imagine the Avalanche firing Roy -- he's a franchise legend, a good friend of general manager Joe Sakic and the team's vice president of hockey operations. But at some point, something has to give, and the days of Roy being hailed as a savior in Colorado already seem a long way in the past.

Dougie Hamilton, Calgary Flames

The season so far: Hamilton was arguably the biggest name traded during the offseason, going from Boston to Calgary in a deal that was widely considered a disaster for the Bruins. The consensus was that the Flames had just landed a future Norris Trophy winner for a handful of magic beans, and they quickly locked him up on a big contract. But one month in, Hamilton has just four points and has seen his usually sturdy possession numbers drop sharply.

Panic time? Hamilton is 22 and has already shown that he can dominate at the NHL level, so he's earned some patience as he adjusts to a new situation in Calgary. Beyond that, Hamilton is a nice reminder that luck plays a big role in perception. His even-strength PDO is a miserable 93.5, and while that stat only goes so far for individual players, it's still a sign that the puck just isn't bouncing well for him.

That said, big contracts bring big expectations, and Hamilton hasn't met them yet. That's bad news if he's on your fantasy team, but we'll give him some more time before we start worrying about his long-term outlook.

Anze Kopitar, Los Angeles Kings

The season so far: After 15 games, Kopitar has just six points.

Panic time? If you're his agent? Probably, given that he still hasn't signed that big extension that we all assumed would be in the neighborhood of a $10 million annual average value. But if you're a Kings fan, no.

Granted, Kopitar is well behind his typical offensive pace. But he's a guy whose contributions can't be measured based on points alone. He's a two-way force who drives possession as well as anyone, and that aspect of his game hasn't slipped this season. The low point total is partly a result of an on-ice shooting percentage of just 6.2 percent at even strength, which would be by far the lowest of his career over a full season. That's despite Kopitar himself shooting 25 percent. In other words, the puck just isn't going in for anyone he plays with, which explains the lone assist on his stat line. That won't continue.

Kopitar is a great player who's suffering through a string of bad luck. He'll be fine and the points will come. (Now Dustin Brown on the other hand ...)

Sidney Crosby, Pittsburgh Penguins

The season so far: We saved the big one for last. Crosby has had the worst start of his career, held pointless on 10 of the Penguins' 15 games. With nine points, the preseason Art Ross favorite ranks outside the league's top 100 scorers today.

Panic time? Of course not. Crosby entered the season as consensus pick as the league's best player, and it's going to take more than one bad month to strip him of that title -- especially when he's still doing stuff like this, let alone this. Crosby will be fine. To even suggest otherwise would be madness.

But while we're here:

Crosby is 28 years old, and in today's NHL that means he's past his prime. That sounds crazy, but the numbers bear it out. Every player is different, and sometimes we see guys like Jaromir Jagr or Teemu Selanne who can play at a high level into their late 30s and beyond. But we've also seen players like Dany Heatley and Vincent Lecavalier dominate in their mid-20s then be all but done as top-six players by their early 30s.

Crosby is far better than Heatley or Lecavalier ever were, of course, and even if he woke up one morning 25 percent worse than his peak, he'd still be one of the league's top players. But it might be time to admit that it's possible -- just possible -- that we've already seen his very best. That's not panic or an overreaction to a minor slump; it's just the reality of how players age in today's league.