As the amount of talent left on the free-agent market dwindles, the most effective way for NHL general managers to make substantial changes to their rosters will be through the trade market.
The teams with the deepest prospect pools will be able to acquire the top stars on the trading block because, with the salary cap going down, adding players on entry-level contracts (such as top prospects making their rookie debuts) is going to be an objective for clubs in a rebuild mode.
Let's look at the top prospects that GMs should consider using as trade bait prior to the start of the 2013-14 season.
Oscar Klefbom is one of the Edmonton Oilers' top prospects and projects to be a top-four defenseman at the NHL level.
But after drafting Sault Ste. Marie Greyhounds D-man Darnell Nurse with the No. 7 pick in the 2013 draft, Klefbom could be used to help general manager Craig MacTavish acquire an NHL player who's already a top-four defenseman.
The Oilers are in win-now mode. After stockpiling young talent with four straight draft picks inside the top seven (including three consecutive No. 1 picks from 2010-12), it's time for this team to start making the playoffs and become a perennial winner.
One of the missing pieces on the Oilers roster that could prevent the team from taking the next step in its development next season is the lack of a top-tier, two-way defenseman who excels against opponents' top scorers.
Acquiring these top-pairing defensemen requires teams to part with top trade assets. But luckily for the Oilers, they have a talented young prospect in Klefbom to offer teams in exchange for a blueliner who would make a strong impact with the NHL club right now and in the future.
The Phoenix Coyotes have exceptional depth and top-tier talent on the blue line at the NHL level, and those same strengths can also be found in their prospect pool.
David Rundblad is the team's second-most talented defenseman prospect after Brandon Gormley, but he has yet to make much of an impact in the pros. The former first-round pick has one goal, seven assists and a minus-17 rating in 38 career NHL games.
With that said, Rundblad still has a lot of value as a young defenseman, with strong puck-moving skills, a powerful shot from the point, the ability to quarterback a power play and impressive offensive awareness.
The Coyotes are a team desperate for more scoring depth at forward, and trading a quality 22-year-old defenseman such as Rundblad is one option for general manager Don Maloney to upgrade an offense that ranked 21st in goals scored and 25th in power-play percentage last season.
Phoenix would be wise to use its superior defensive depth to bolster an offense that isn't strong enough to carry the team deep into the playoffs.
Joe Morrow was traded for the second time in four months when the Boston Bruins acquired him as part of the deal that sent former No. 2 overall draft pick Tyler Seguin to the Dallas Stars.
Morrow, who was a 2011 first-round pick of the Pittsburgh Penguins, joins a group of impressive young Bruins defensemen who will be competing for ice time on the second and third pairings on the NHL roster next season.
The problem for him is that there are three quality defensemen already ahead of him in Boston. Torey Krug and Matt Bartkowski played important roles in the Bruins' playoff run last year. They gave the team some of the playmaking, puck-moving and scoring production that the blue line lacked for most of the regular season. Former ninth overall pick Dougie Hamilton also had a good rookie campaign and is more NHL-ready than Morrow.
This situation creates the possibility that Morrow could be traded again, because it's difficult to see him cracking the Bruins roster any time soon.
That doesn't mean he's not going to be a quality NHL player someday, though. He has the talent needed to be a top-four defenseman, but he has more value to the Bruins as a trade asset that could be included in a deal for an impact player that would help Boston make another run to the Stanley Cup.
The Minnesota Wild could be in a position to make a deep run in the Western Conference playoffs next season if they acquire another impact player on the blue line.
One position of strength in the organization that may be used to add another star via trade is goaltending. With Niklas Backstrom, Josh Harding and 23-year-old Darcy Kuemper giving Minnesota a solid trio of netminders at the NHL level, top prospect Johan Gustafsson could be used as trade bait to add a top-six forward or top-four defenseman.
Gustafsson went 20-13 with a .932 save percentage for Lulea HF of the Swedish Elite League last season, which are very impressive numbers for a young goaltender in one of the world's top professional leagues.
If the Wild decided to ever trade Gustafsson, the return would have to include an established NHLer with more than one year of term on his contract (not a rental).
Tomas Tatar is an undersized forward at 5'10", but he has exceptional offensive talent and impressive speed.
The 22-year-old forward finished second on the AHL's Grand Rapid Griffins in scoring last year with 49 points (23 goals, 26 assists) in 61 games. In the 2011-12 season, he tallied 58 points in 76 games.
Tatar is a quality left winger who's ready to make an impact at the NHL level following four full seasons in the AHL. But he's not going to fulfill a top-six role on the Red Wings roster next year.
Even after signing free-agent forwards Stephen Weiss and Daniel Alfredsson this summer, Detroit is still another top-four defenseman and a little scoring depth away from making a realistic push for the Stanley Cup from the Eastern Conference next season.
One of the team's best assets to acquire an impact player before the start of the 2013-14 season is Tatar.
In the event that he's traded, his spot on the Griffins roster would likely be taken by top prospect Teemu Pulkkinen, who has the potential to be a top-six NHL forward.
The Pittsburgh Penguins have one of the best groups of young defensemen prospects in the NHL, including former first-round picks Olli Maatta and Derrick Pouliot. General manager Ray Shero was unwilling to part with these two players before last year's trade deadline, and there's no reason to suggest that strategy will change in 2013-14.
In that case, one of the second-tier defensive prospects with a bright NHL future who the Penguins could trade for additional NHL depth is Scott Harrington.
The 20-year-old has enjoyed a successful career in the OHL for the London Knights as a solid two-way defenseman with impressive playmaking skills and a high hockey IQ. He also brings a physical element to the ice and is capable of excelling defensively against opposing teams' best forwards.
Harrington is the type of prospect who could help Pittsburgh acquire a top-six forward or a veteran defenseman capable of strengthening the team's chances of reaching the Stanley Cup Final. As one of the top championship contenders in the Eastern Conference, expect the Penguins to explore many ways to improve their team through trades before next season's deadline.
The Philadelphia Flyers have tremendous talent at center with Claude Giroux, Vincent Lecavalier and Brayden Schenn giving head coach Peter Laviolette strong depth down the middle.
The most glaring weakness on the Flyers roster is the lack of a top-pairing, shutdown defenseman. Unfortunately for Philadelphia, it doesn't have many top-tier prospects to dangle in the trade market in hopes of acquiring a top-four defenseman.
But one player with value is Scott Laughton. The 20-year-old center was impressive in five NHL games last year before being sent back to the OHL's Oshawa Generals, where he tallied 56 points (23 goals, 33 assists) in 49 games.
Laughton has the potential to be a top-tier defensive center because of the strong awareness he shows in his own end, the physicality he plays with and his high hockey IQ.
If general manager Paul Holmgren needs to make a major trade to strengthen his roster before next season, Laughton is his top prospect to offer.
Nicholas Goss is an NHL Lead Writer at Bleacher Report. He was also a credentialed writer at the 2011 and 2013 Stanley Cup Final, as well as the 2013 NHL draft.