The NHL coaching carousel was particularly busy last summer, with nine head coaching changes in the offseason.

Measuring the impact of a new head coach is tricky because it’s not the only change those nine teams made. It’s a balancing act between player growth, personnel changes and tweaks to the support staff. So instead, let’s check the vibes around each team with a new bench boss to spot early differences, directions and trends developing over the first month-plus of NHL action.

Joel Quenneville, Anaheim Ducks

11-4-1 Record

Last year, it was Lukáš Dostál against the world in Anaheim. The defense was among the worst in the league, leaving him completely exposed on a nightly basis. And the offense, despite having a lot of potential, was bottom-10 in the league. That was a general theme of the Greg Cronin era, with many players’ progress stalling out.

That has already changed through the first month-plus of action. The Ducks’ defense, across 16 games, is still an issue, with the team allowing a league-high rate of 3.24 xG against at five-on-five. But to Anaheim’s credit, that has trended down over this last stretch of play, which has given the goalies more support.

The real story is the Ducks’ offense popping. That’s thanks to two things — natural progression from the likes of Leo Carlsson, Cutter Gauthier, Mason McTavish and Beckett Sennecke, among others, after the offense was suppressed under the last staff, and strategic changes. Anaheim is incorporating more speed and pace into its attack, which is evident in how this team creates chances off the rush and pressures for turnovers.

It’s a more fitting playing style, considering the dynamic skill on this roster, and it’s helping this team outpace defensive mistakes. That has led to early wins over expected contenders such as the Jets, Golden Knights, Stars, Devils and Panthers.

Glen Gulutzan, Dallas Stars

9-4-3 Record

The Stars are in a very different position compared to teams such as the Ducks, Blackhawks or even the Bruins. This isn’t a rebuilding or retooling club looking for a new direction; this is a bona fide contender that needed a new voice after falling short in three straight conference finals.

In Glen Gulutzan, the Stars found a new old voice. After a dozen years away from the organization, he is back for his second stint as head coach in Dallas. He brings more seasoning and playoff experience after helping lead the Oilers over the Stars in each of the last two postseasons.

Systematically, the Stars don’t need a drastic overhaul. But there is still room for Gulutzan to tweak this team’s approach and prepare it for a deeper postseason run. Those seemingly minor details can add up for a team, especially when it matters most. It starts with defensive zone adjustments to give the Stars’ blueliners more support, which has helped Dallas limit shots and scoring chances against to open the season. And it extends to the offensive end, where the head coach is pushing his team to be tougher on the puck, to extend zone time. There have been glimpses of that so far, but that’s where this team still has room to grow — especially after a lack of five-on-five scoring led to its demise in each of the last two postseasons. As the forward group gets healthy, the pieces should start falling into place, giving more dimension to a team that tends to rely heavily on the rush.

Dan Muse, Pittsburgh Penguins

9-5-3 Record

Dan Muse is one of the three first-time NHL head coaches hired this summer. He brings a fresh perspective and adaptability to Pittsburgh — two elements that set him apart from a lot of the coaching carousel.

The Penguins came into this season projected to land in 30th with just 76 points. So an 8-2-2 record in October was a real surprise. While this team is coming back to reality, with four losses in five games so far this month, there are still some positives.

One difference, according to Erik Karlsson, as reported by The Athletic’s Josh Yohe, is that the players know what’s expected of them. “You do the things you’re good at, and not the things that someone tells you to do, that you can’t do,” Karlsson said.

That seems to be helping get Karlsson’s offense back on track. But maybe the most eye-catching is Evgeni Malkin’s rebound. He has scored at an impressive pace of 4.18 points per 60 through 17 games, up from last year’s career-low rate of 2.48. Malkin’s second-line presence has given the team a second wave behind Sidney Crosby. So has the emergence of up-and-comers such as Ben Kindel, who has worked his way up the lineup. And those positive vibes extend to the back end, where Ryan Graves is having a bounce-back season alongside Connor Clifton.

Marco Sturm, Boston Bruins

11-7-0 record

Marco Sturm was hired to help lead this next chapter of Bruins hockey after management kicked off a retool at the last trade deadline. During the first stretch of the season, the results were to be expected of a team in this position. But after a 7-2 loss to the Senators, this group has started to turn things around, with a seven-game winning streak — and Sturm’s defensive direction seems to be a key part of it.

The Bruins run a man-to-man system, and the idea is to create layers of coverage to protect the middle of the ice. This strategy agrees with players such as Charlie McAvoy and Nikita Zadorov, who the team needed to rebound after some lows last season. That was on display against the Hurricanes during this streak. The Canes attempted 54 five-on-five shots, 19 of which were blocked. And only seven of those attempts, according to Natural Stat Trick, came from the higher-danger areas of the ice. As the heat map below shows, Boston was able to limit Carolina from concentrating its shots to the middle of the ice.

Via Natural Stat Trick

Take this third-period shift, where the Bruins limit the Canes to just two shot attempts while defending a 1-0 lead.

The first attempt misses the net. McAvoy blocks the second and helps Boston shift to offense, which leads to a Viktor Arvidsson goal.

Jeff Blashill, Chicago Blackhawks

8-5-3 Record

It takes time for a new coach’s system to take hold. After training camp, it becomes an ongoing process where players learn on the fly. That’s when more details can be worked in, and a young team such as the Blackhawks can start building a new identity.

The process is far from perfect in Chicago through the first month of play. The team is still allowing a high rate of shots and chances, even with the shift from zone defense to a hybrid system. The difference now, compared to last season, is that as the defenders and forwards learn to push opponents to the outside, the goaltending has provided them with more leeway, thanks to some really strong play in net. Ahead of Wednesday’s matchup, Spencer Knight and Arvid Söderblom only allowed 1.98 goals against per 60 at five-on-five.

And unlike last season, the team has been scoring at a higher clip, too. Similar to the Ducks, some of that is thanks to the progression of up-and-coming players such as Connor Bedard and Frank Nazar. But the new emphasis on speed — which some players feel is becoming a part of their identity — has also contributed. The team is averaging more 22-plus mile-per-hour speed bursts per game compared to last year, according to NHL EDGE data, which has helped this team create more rush chances. As a result, their xG creation has jumped from 2.17 per 60 to 2.67.

Lane Lambert, Seattle Kraken

7-4-5 Record

Lane Lambert made a name for himself as an elite assistant coach alongside Barry Trotz. While he struggled in his first head coaching experience on Long Island, he proved that he could still coach outside of Trotz’s shadow as a part of Craig Berube’s staff in Toronto.

The big question surrounding Lambert is whether he is more of a specialist who belongs in an assistant/associate role or whether he has the chops to lead.

Lambert’s start in Seattle has been interesting so far because the team is playing to his strengths from previous assistant roles (and not his time as the Islanders’ head coach). While there’s still work to do in the net-front area, the Kraken have allowed fewer scoring chances from the middle of the ice and the left circle at five-on-five. That’s put the goaltending in a position to succeed with a collective .932 save percentage through 16 games at five-on-five. The penalty kill has allowed a high rate of goals against, but there is a lot more promise below the surface.

But what is really holding this team back, unlike Lambert’s Islanders, is the offense. The Kraken aren’t generating a high rate of shots or chances, and rank dead last in the league in five-on-five scoring. While the roster has its limitations and has been strained by injury at times, the coaches haven’t tapped into the depth approach that helped this team shine a few seasons back.

Rick Tocchet, Philadelphia Flyers

8-5-2 Record

A general theme for rebuilding teams is defensive-zone issues. The Flyers are the exception to that, with structure to build on from the last few years. So far this season, the team is suppressing more shots, and its xG against is relatively consistent compared to last year. The most noticeable difference on the back end is that this team is getting saves. Last year, the Flyers had the worst collective save percentage (.891) in the league at five-on-five.

The problem is balancing out that defensive zone structure with more offensive pop. Philadelphia has generated only 2.31 xG per 60, which ranks third last in the league, ahead of only the Kraken and Sharks. That’s a difference of 0.32 from last season, and it’s noticeable without a ton of finishing talent to outpace it.

What’s behind the Flyers’ disjointed offense? As The Athletic’s Kevin Kurz reported last week, it’s the fact that there’s an offensive system at all. In past years, this group was instructed to let creativity lead the way in the offensive zone and make instinctive reads. So to better adjust to this new-look system, the coaches had to simplify things.

The learning process doesn’t happen overnight, but it will be interesting to see how this group starts to grasp it. Because even with the roster’s ceiling in mind, Tocchet’s teams haven’t always been dynamic offensively at five-on-five. So, his time in Philadelphia could also be a test of his strategies.

Mike Sullivan, New York Rangers

8-7-2 Record

The early home and away splits are extreme and weigh down the Rangers’ record so far. But the process below the surface shows signs of progress under this staff.

One of the most pressing issues for Mike Sullivan to fix was the Rangers’ five-on-five play, which has been a shortcoming for years. Under his direction, the team is embracing a north-south style, a 1-2-2 forecheck and focusing more on their cycle game to extend zone time after being so dependent on quick rushes. It hasn’t consistently translated on the scoresheet over the last 17 games (especially on home ice), but the Rangers’ scoring chance generation is up to an xG rate of 2.83 per 60, from last year’s 2.56.

Roster flaws are going to hold this team back; there aren’t enough finishers up front, and the back end is missing puck-movers. Still, the coaches are finding ways to maximize the group they have, after the Rangers bled rush shots against last year. It starts at the top with Adam Fox and Vladislav Gavrikov, who are excelling on the top pair, and Will Borgen, whose defense has rebounded. Those improvements, paired with more puck control up front, have helped the team lower its xG rate against from 2.80 per 60 last year to 2.16.

Adam Foote, Vancouver Canucks

8-9-1 Record

Of the nine teams with a new head coach, the Canucks are the only one to hire from within. Adam Foote was an assistant coach in Vancouver who ran the defense and penalty kill on Tocchet’s staff.

The familiarity factor doesn’t always work out. But it can make for a strong fit, too; Rod Brind’Amour is the shining example of that, seven years in with the Canes, and Scott Arniel is a more recent example.

So far, there are both pluses and minuses to the start of the Foote era in Vancouver. A big question under Tocchet was whether the Canucks had enough substance behind their goal scoring. While it hasn’t always translated on the scoresheet this season, the team is creating more quality looks with an xG rate of 2.74 per 60, and experimenting with different end-game tactics.

What is a bit more surprising, considering Foote’s playing career and role with the Canucks before taking over as head coach, is how much this team is allowing back. Puck management has been a theme throughout the first month of action. The numbers track that with a higher rate of shots against and the second-worst rate of quality chances allowed (3.20 xG per 60).

What makes Vancouver particularly challenging to assess is the number of key injuries so far this season, which have weakened an already flawed roster. So it’s going to take time to really dig into whether Foote is the right coach to get this team back on track after last season’s chaos.

— Data collected before Wednesday’s matchups, via Evolving-Hockey, HockeyViz, Hockey Stat Cards, All Three Zones and Natural Stat Trick. This story relies on shot-based metrics; here is a primer on these numbers.