With the 2014-15 season complete, NHL.com looks at some of the biggest storylines and award contenders.

It has been an unpredictable season for the top defensemen in the NHL.

Injuries have derailed the chase for the Norris Trophy for Mark Giordano of the Calgary Flames, Kris Letang of the Pittsburgh Penguins, Kevin Shattenkirk of the St. Louis Blues and Victor Hedman of the Tampa Bay Lightning. Zdeno Chara of the Boston Bruins finished second in the voting last season and while he too was injured, was probably not going to be part of the discussion anyway.

Nashville Predators defenseman Shea Weber was considered a favorite for the award shortly after Giordano was injured, but his team faded at the end of the season and several advanced statistics don't agree with that sentiment.

Before the season, Drew Doughty of the Los Angeles Kings was pegged as the favorite by NHL.com. Doughty has never won the trophy, but the argument that he was the best defenseman in the sport became a popular one while the Kings marched to their second Stanley Cup title in three years last spring.

Doughty has had a phenomenal year, especially considering the amount of ice time he had to shoulder while the Kings dealt with injuries to Jake Muzzin and Alec Martinez, and Slava Voynov being suspended for 76 games. He would be a fine choice for the 2015 Norris Trophy, but he is not the pick for NHL.com.

That would be Ottawa Senators talisman Erik Karlsson . Though Karlsson led all defensemen in points with 66 that is not the primary reason he deserves to win the Norris Trophy for the second time in his career.

Karlsson's shot attempt percentage (SAT%) was 16th among 60 defensemen who logged at least 1,250 minutes of ice time at even strength. His SAT% relative to his team's average ranked eighth among those 60 players.

The website War-on-Ice.com has introduced an attempt to quantify scoring chances during the 2014-15 season and Karlsson stands out. Despite Doughty playing 83 more minutes at even strength this season, Karlsson was on the ice for 11 more scoring chances for his team.

Critics of Karlsson lament his perceived defensive deficiencies, but the percentage of scoring chances when Karlsson was on the ice at even strength was higher for the Senators than it was for the Kings with Doughty, the Chicago Blackhawks with Duncan Keith and the Montreal Canadiens with P.K. Subban.

All of these are team-based metrics, of which an elite defenseman like Karlsson provides plenty of influence. His individual numbers are extraordinary.

Karlsson had 292 shots on goal, 28 more than any other defenseman and WAR on Ice credited him with 128 individual scoring chances, 24 more than the others at his position.

Karlsson has the most points, which always rates highly with Norris voters, and he was very productive during the second half of the season when Ottawa made its incredible playoff push. Those are two reasons why he might win the award, but there is more on his resume to support a second Norris Trophy than just most points and a strong finish.

FINALISTS

Drew Doughty, Los Angeles Kings -- Doughty's chances of winning the Norris for the first time

Drew Doughty Defense - LAK GOALS: 7 | ASST: 39 | PTS: 46

SOG: 219 | +/-: 3

probably took a big hit when the Kings did not make the Stanley Cup Playoffs. That's unfortunate and should not be the reason to not vote for him. Doughty was amazing this season, playing 29 minutes per game and still driving puck possession better than any player who tried to log that amount of ice has been able to.

Among the 60 defensemen who played at least 1,250 minutes this season, the only one with a better SAT% was Muzzin, who is often Doughty's partner with Los Angeles. Like Weber, there has been the idea put forth that Doughty "deserves" a Norris Trophy because he is so great. The problem is, in some years, there are several defensemen who play well enough to "deserve" the Norris, and this season is no exception.

P.K. Subban, Montreal Canadiens -- Subban is another player who has played well enough to win the award and it is possible he will earn a second Norris Trophy. The Canadiens have been a below-average puck possession team but not when Subban is on the ice. His SAT% relative to his team's

P.K. Subban Defense - MTL GOALS: 15 | ASST: 45 | PTS: 60

SOG: 170 | +/-: 21

average (SAT%rel) is the best among those 60 defensemen with 1,250 minutes of even-strength ice time. He finished with 15 goals and 60 points (tied for second behind Karlsson) and finished sixth in time on ice per game.

The list of strong candidates for this award continues to be, like last season, into the double digits. Though teams are more eager to roll four lines and create equality among forwards, the best defensemen remain workhorses and there may be more elite players at the position in the League than ever before.

Others who don't fit in NHL.com's final six but deserve recognition include Letang, Weber, Anton Stralman of the Tampa Bay Lightning and Nick Leddy of the New York Islanders, just to name a few.

Also in the mix: Justin Faulk, Carolina Hurricanes; Mark Giordano, Calgary Flames; Duncan Keith, Chicago Blackhawks