With the 2015-16 NHL season under way, an offseason of roster tinkering and overhauls by general managers has ended. The marginal rise in the salary cap, from $69 million to $71.4 million, affected their efforts to invest in their lineups. For some clubs, there's not much cap payroll remaining for potential upgrades during the season.

Several teams, including the defending Stanley Cup champion, the Chicago Blackhawks, could find themselves handcuffed by limited salary-cap space. They won't have enough cap room to upgrade from within via free agency or trades.

The following slideshow lists the NHL teams with the worst salary-cap issues for 2015-16, examining their available cap space, efforts to create more room and the possible effects over the course of the season. Weigh in with your opinion in the comments section below.

Boston Bruins

The Boston Bruins entered this season carrying over $71.8 million in actual total salary for 2015-16. As of Oct. 10, their salary-cap hit was $70,194,000, giving them $1.206 million in cap space.

In his first offseason as general manager, Don Sweeney made several significant cost-cutting deals. He shipped defenseman Dougie Hamilton to the Calgary Flames, dealt winger Milan Lucic to the Los Angeles Kings, moved right wing Reilly Smith and the rights to Marc Savard to the Florida Panthers for forward Jimmy Hayes and signed winger Matt Beleskey.

However, the Bruins have limited cap space to address their thin defense corps. With veteran Dennis Seidenberg sidelined by back surgery, they will get some short-term cap relief if they place him on long-term injured reserve. Still, that could prove insufficient to address their blue-line needs over the course of the season.

Chicago Blackhawks

The Chicago Blackhawks are carrying over $83.8 million in actual total salary, but their salary-cap payroll (as of Oct. 10) is $71.050 million. That puts them uncomfortably close to the $71.4 million cap ceiling. 

General manager Stan Bowman was busy shedding salary in the offseason. Among his moves was trading away forwards Patrick Sharp and Kris Versteeg. On Oct. 3, Bowman placed left wing Bryan Bickell ($4 million cap hit) on waivers, but he remained on the roster after going unclaimed. Defenseman Michal Rozsival ($600,000) is on long-term injured reserve.  

The cost-cutting efforts could affect the Blackhawks' depth this season. Bowman doesn't have much room to promote from within or add experienced depth via trade or free agency. If he goes the trade route, he could be forced to accept dollar-for-dollar deals. That could seriously hinder the Blackhawks' hopes of defending their title.

Minnesota Wild

The Minnesota Wild enter this season carrying over $73 million in actual total salary. As of Oct. 10, their total salary-cap payroll was just over $70.8 million, leaving them very close to the cap ceiling. 

Goaltender Niklas Backstrom ($3,416,666 cap hit) is the reason why the Wild have limited cap room. On Sept. 10, the Minnesota Star Tribune's Michael Russo reported an elbow injury prevented them from buying out the veteran netminder in the offseason. They are forced to carry three goalies—Backstrom, starter Devan Dubnyk and backup Darcy Kuemper) for this season.

Unless the Wild can find a way to shed part or all of Backstrom's cap hit, it will eat up valuable salary-cap room that could be better spent on roster additions later in the season. Unfortunately, his no-movement clause prevents demotion to the minors, while his limited no-trade clause could hamper efforts to deal him away.

New York Rangers

The New York Rangers are carrying over $81.555 million in actual total salary. As of Oct.10, their total salary-cap payroll is just less than $71.25 million, bumping up against the league ceiling.

Limited cap room and the need to re-sign center Derek Stepan forced Rangers management to make a couple of cost-cutting offseason deals. Restricted free-agent winger Carl Hagelin was traded to the Anaheim Ducks for the more affordable ($850,500) Emerson Etem. Backup goalie Cam Talbot ($1.45 million) was dealt to the Edmonton Oilers for three draft picks. 

While the Rangers kept their roster core intact for 2015-16, they've left themselves little room to take on additional talent if required later in the season. That could hamper their Stanley Cup aspirations.

Philadelphia Flyers

The Philadelphia Flyers are carrying over $71.3 million in actual total salary for 2015-16. As of Oct. 10, their total salary-cap payroll was just over $70.7 million, leaving them with roughly $670,000 in salary-cap space.

General manager Ron Hextall recently raised eyebrows by demoting defenseman Andrew MacDonald ($5 million annual cap hit), even though the actual cap saving was only $950,000. On June 27, he freed up much-needed cap space by shipping defenseman Nicklas Grossmann and the rights to Chris Pronger to the Arizona Coyotes for forward Sam Gagner. 

Hextall is trying to free up cap room and roster spots for young, affordable talent. However, the Flyers are also stuck with expensive fading veterans such as forwards Vincent Lecavalier and R.J. Umberger, whose contracts are difficult to move. They will continue to hinder Hextall's rebuilding efforts this season.

San Jose Sharks

The San Jose Sharks enter this season carrying over $71.6 million in actual total salary for 2015-16. As of Oct. 10, their total salary-cap payroll was just over $70.109 million, leaving them with just over $1.290 million in cap space. 

Sharks general manager Doug Wilson tinkered with his roster in the offseason, signing veteran winger Joel Ward and defenseman Paul Martin as unrestricted free agents and acquiring goaltender Martin Jones via trade. Those moves added over $11 million to their payroll. The Sharks are also carrying aging stars Joe Thornton and Patrick Marleau, whose combined cap hit is over $13 million.

If the additions of Ward, Martin and Jones fail to improve the Sharks, Wilson won't have much room to address the problem. They won't get cap relief from Raffi Torres' 41-game suspension. Should the production of Thornton and Marleau also decline, this season could turn into a nightmare for the Sharks.  

Tampa Bay Lightning

The Tampa Bay Lightning enter this season carrying over $76 million in actual total salary for 2015-16. As of Oct. 10, their total salary-cap payroll was just over $70.505 million, leaving them with roughly $894,000 in cap space.

The Stanley Cup finalist in 2015, the Lightning didn't make any significant roster moves during the offseason. Considering their depth in established talent, such as Steven Stamkos, Ryan Callahan and Ben Bishop, and their rising stars, such as Tyler Johnson, Victor Hedman, Ondrej Palat and Nikita Kucherov, that was understandable. They're keeping this core intact for another run at a championship next spring.

While the Lightning are considered a Cup contender, they don't have much space to improve their depth if necessary later in the season. Management might have to consider dollar-for-dollar swaps if they wish to boost their Cup hopes.

Toronto Maple Leafs

The Toronto Maple Leafs enter this season carrying over 82.2 million in actual total salary for 2015-16. As of Oct. 10, their total salary-cap payroll was just under $70.4 million. That leaves them with over $900,000 in cap space. 

A long overdue rebuild is currently underway with the Leafs, who shook up their front office and coaching staff. Trading Phil Kessel to the Pittsburgh Penguins for a return made up largely of draft picks and prospects was their only significant offseason roster move. They made inexpensive, short-term additions in Michael Grabner, Pierre-Alexandre Parenteau, Brad Boyes and Martin Marincin via trade and free agency.

Expensive core players such as Dion Phaneuf, Joffrey Lupul and Tyler Bozak remain in the lineup. While the Leafs aren't expected to be a postseason contender in 2015-16, continuing to carry high-salaried players could affect efforts to add younger, more affordable talent over the course of the season.

Vancouver Canucks

The Vancouver Canucks are carrying over $73.5 million in actual total salary. As of Oct. 10, their salary-cap hit was over $71.2 million. That's because goalie Richard Bachman was an emergency call-up to replace sidelined backup Jacob Markstrom.

General manager Jim Benning is attempting to rebuild an aging roster that includes the Sedin twins, Henrik and Daniel ($14 million combined), and goalie Ryan Miller ($6 million). During the offseason, defenseman Kevin Bieksa and goalie Eddie Lack were traded in cost-cutting deals. Center Linden Vey ($1 million) was recently demoted, while defenseman Frank Corrado was claimed off waivers by the Toronto Maple Leafs. 

Benning cleared room for promising and affordable youngsters such as forwards Jake Virtanen and Jared McCann. If those kids struggle this season, he won't have much cap room to improve the roster by adding experienced depth through trades or free agency.

Washington Capitals

As of Oct. 10, the Washington Capitals are carrying over $70.7 million in actual total salary and salary-cap payroll. Center Nicklas Backstrom ($6.7 million annual average salary) is currently on injured reserve, but his salary still counts against their cap.

The Capitals made several notable offseason moves to improve their roster. They shipped Troy Brouwer, a draft pick and prospect to the St. Louis Blues for winger T.J. Oshie ($4.175 million cap hit) and signed veteran right wing Justin Williams ($3.25 million) as a free agent. They also re-signed goaltender Braden Holtby to a five-year, $30.5 million contract.

For a team aspiring to a championship run this season, the Capitals' limited cap space could become a problem. Though they stabilized their goaltending and bolstered their depth at right wing, they lack sufficient room to make further additions if necessary over the course of the season. 

Except where indicated, player and team info via NHL.com. Salary info via General Fanager.