Sharks' recent success of little surprise to analytics community

Behind the Numbers is a weekly series where NHL.com examines both player and team trends with an emphasis being placed on advanced statistics. This week, we look at how the San Jose Sharks climbed up the NHL standings after a slow start to the regular season.

The roots of the San Jose Sharks' climb to near the top of the Western Conference were evident, if examined closely enough, during the struggles that plagued them in the first two months.
The Sharks (28-14-7, 63 points) have gone 16-4-2 in their past 22 games, second-best in the NHL behind the Tampa Bay Lightning (17-2-1) since Dec. 2.
There were questions about whether such a run would be possible after the Sharks lost 6-2 at the Ottawa Senators on Dec. 1, a game that marked the return of defenseman Erik Karlsson, who had been traded from Ottawa to San Jose on Sept. 13, 2018.
San Jose was 12-10-5, a record completely unexpected for a team that had reached the Stanley Cup Playoffs in 13 of the previous 14 seasons and made a blockbuster trade to add a two-time Norris Trophy winner to its defense.
During the 6-2 loss, Karlsson had a season-high nine shots on goal and the Sharks outshot the Senators 38-26.

In the aftermath, coach Peter DeBoer said the Sharks had to "get that swagger back," expressing some of the frustration and doubt the players were experiencing.
When pucks aren't going in the net, it does a lot to affect perception, even from those inside the team. Wins and losses are important because the resulting points determine standings position, but examining the bigger picture can often provide clues about how a team's fortunes might change.
As mediocre as San Jose's record was, there were legitimate reasons to be optimistic. Through those first 27 games, the Sharks ranked second in the NHL in percentage of shot attempts (55.75) but were 26th in 5-on-5 shooting percentage (6.7) and last in 5-on-5 save percentage (.893).
Shooting and save percentages are among the analytical measures that can flip quickly because they are based on goals.
The Sharks, an established veteran team, hovered around the middle of the pack in those categories during the previous three seasons. From 2015-16 through 2017-18, they were 10th in SAT percentage (51.22), 13th in 5-on-5 shooting percentage (7.7) and 23rd in 5-on-5 save percentage (.921).
Some teams may not have the talent necessary to score consistently or may have subpar goaltending, and those circumstances can result in below-average combined shooting and save percentages. But the Sharks did not appear, in an examination of their underlying numbers, to be such a team.
They haven't been since the game in Ottawa. In fact, they have their swagger back.

The Sharks are still getting 55.50 percent of the shot attempts during their past 22 games, so that hasn't really changed, but they are shooting 11.5 percent at 5-on-5, best in the NHL since Dec. 2. San Jose's 5-on-5 save percentage in that span is .910, 21st in the NHL, but 10 spots higher than its pre-Dec. 1 ranking.
Karlsson's fortunes have mirrored those of his team. Through the first 27 games of the season, Karlsson was on the ice for 59.55 percent of 5-on-5 shot attempts and had 15 points in 27 games, production well below his typical output in Ottawa, where he averaged 71 points per season during the previous five seasons.
Since Dec. 2, the Sharks have been getting 59.42 percent of the 5-on-5 shot attempts with Karlsson on the ice and his point production has taken off. Although Karlsson missed two games in December because of a suspension, he has 28 points (one goal, 27 assists) in his past 20 games. When shots created are getting converted into goals, it becomes a different game.
The Sharks also have the luxury of having two incredibly productive defensemen. As great as Karlsson has been, Brent Burns has put up 25 points (six goals, 19 assists) in his past 22 games and leads all defensemen in scoring with 52 points (nine goals, 43 assists) this season. Naturally, the Sharks had high expectations for their defense duo coming into the season and it has taken some time, but they've lived up to the hype.
Burns and Karlsson have combined for 95 points, far and away the most by any defense teammates, ahead of Mark Giordano and Noah Hanifin (72) of the Calgary Flames, Morgan Rielly and Jake Gardiner (71) of the Toronto Maple Leafs, and Mattias Ekholm and Roman Josi (70) of the Nashville Predators.
Though it's entirely reasonable for the Sharks to expect major production from Burns and Karlsson -- they are, by a wide margin, the two highest-scoring defensemen during the past 4 1/2 seasons -- the real Sharks team probably sits somewhere between the two extremes displayed this season. The Sharks may not be the best shooting team in the NHL, but they're probably not near the worst either.
But these Sharks are precisely why team evaluation shouldn't be based on goals or wins over small sample sizes.
Through the first third of the season, San Jose was stumbling along with a below-average record and negative goal differential, and now the Sharks are Stanley Cup contenders.