The first expansion draft in the salary-cap era has even the most seasoned NHL general managers unsure of what is going to happen over the next few weeks.

''You expect the unexpected,'' Toronto Maple Leafs GM Lou Lamoriello said.

The most unpredictable and fascinating offseason in more than a decade has arrived. Uncertainty runs from the Vegas Golden Knights' expansion draft next week through the New Jersey Devils' decision with the top pick in the entry draft to a free agent market that hinges significantly on how much the salary cap goes up - if at all.

Trades could be coming fast and furious as Vegas GM George McPhee stockpiles assets in exchange for agreeing to select or not select players in the June 21 expansion draft. Teams have to decide who to protect - seven forwards, three defenseman and a goaltender or eight skaters at any position and a goaltender - and there should be some roster juggling around the league before protected lists must be submitted Saturday afternoon.

''I expect something to transpire and the expansions that I've been through in the past, it certainly does,'' Lamoriello said. ''When there are decisions that have to be made, you'd rather make them proactive rather than reactive. People are going to be trying to do things, whether they have one too many defensemen or whether they have one too many forwards or whether they have needs that they could possibly correct by taking a surplus off somebody else.''

The back-to-back Stanley Cup champion Pittsburgh Penguins have to make a quick decision with goaltender Marc-Andre Fleury ahead of the expansion draft because they can't afford to lose 23-year-old Matt Murray , who's 22-9 in consecutive title runs with a 1.95 goals-against average and .928 save percentage and is under contract for three more years. Fleury has a no-movement clause in his contract so he must agree to waive it to be traded or exposed in the expansion draft.

After talking to his colleagues around the league, McPhee said he believes the expansion draft will be more productive for the franchise's future than he first thought.

''There are teams that really want to protect some people and protect their rosters and they are willing to pay a pretty fair price to get us to lay off certain people and go in a different direction,'' McPhee said. ''So in those instances we'll be able to get young players or some draft picks that will help us down the road.''

The expansion draft is drawing so much interest that a group of University of Toronto researchers put together a tool they say shows the optimal protections and picks. Vegas, for its part, hired as a hockey operations analyst General Fanager founder Tom Poraszka, who made the first online expansion draft simulator.

Once all 30 protected lists are revealed on Sunday, Vegas has a 72-hour window to negotiate with any unprotected restricted or unrestricted free agents and make its selections, which will be announced June 21. McPhee wields a lot of power because of that, and it's fair to wonder how he'll put together an expansion roster from scratch.

''I'm not sure George is going to be willing to tell me what player he wants,'' said Washington Capitals GM Brian MacLellan, who was McPhee's assistant for seven years. ''It's frustrating you're going to lose a good player with the expansion draft and you're going to have to react to it.''

The entire NHL is going to have to react to what Vegas does and to the salary cap, which could remain flat at this past season's $73 million or go up, perhaps to roughly $77 million, depending on whether players elect to use their escalator clause to increase it by up to 5 percent. That's a complicated issue and there is no guarantee players raise the cap as much as possible this time around, especially with a new team coming in.

That could alter free agency, which begins July 1. MacLellan acknowledged he would have a more legitimate chance to re-sign 30-goal scorer T.J. Oshie if the cap is at $77 million. And if not, Oshie could be among the most sought after free agents.

Some things to watch this offseason:

NICO OR NOLAN

With the top pick, the Devils are expected to decide between centers Nolan Patrick and Nico Hischier or trade down. There's no franchise-changing star in this draft like Connor McDavid or Auston Matthews, and Patrick's injury-plagued season made this a debate to watch at the draft that begins June 23 in Chicago.

ONE MORE COACH

With the Florida Panthers hiring Bob Boughner, just one coaching vacancy remains: the Buffalo Sabres. Penguins assistant Rick Tocchet and Nashville Predators assistant Phil Housley are believed to be among the candidates, while Washington associate coach Todd Reirden is also in the mix.

FURIOUS MOVES

Because a lot of teams will wait to re-sign players until after the expansion draft, there could be a flurry of activity beginning June 22. Jaromir Jagr's status in Florida and Joe Thornton's in San Jose could be decided before either becomes an unrestricted free agent.

CONTRACT WATCH

Beyond this year's thin crop of unrestricted free agents, led by defenseman Kevin Shattenkirk and wingers Patrick Eaves and Thomas Vanek, teams can begin re-upping potential 2018 free agents on July 1. That means the focus is on the New York Islanders with captain John Tavares, the Montreal Canadiens with Carey Price and the Oilers with McDavid.

CAPPED-OUT BLACKHAWKS

Even if Chicago gets the much-rumored deal done to let Vegas take defenseman Trevor van Riemsdyk to shed the contract of center Marcus Kruger, the Blackhawks have to do some more maneuvering to get under the cap. That could mean the loss of a player perhaps even as good as Niklas Hjalmarsson.

THREE-PEAT

GM Jim Rutherford may have to get creative to help Pittsburgh try to become the first team to win the Cup in three consecutive years since the Islanders' dynasty years from 1980-83. Among the Penguins' free agents are Nick Bonino, Chris Kunitz and Trevor Daley.

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AP Hockey Writer John Wawrow in Buffalo, New York, contributed.

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Follow Hockey Writer Stephen Whyno on Twitter at http://www.twitter.com/SWhyno .

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