george_gl

The NHL is not a buy now, pay later operation. There's no such thing as credit where the salary cap is concerned. If you want the player, you have to have the cash. Sometimes a team can find itself with too much in its cart when it gets to the till which then results in a few items getting returned. It's the black and white truth of today's NHL.
George McPhee has been able to amass a roster loaded with talent. But talent is expensive and while McPhee has signed a plethora of value contracts, he found himself tipping the salary cap scale at a number a touch too high.
In order to get compliant with the cap, McPhee first moved Erik Haula to Carolina and took back Nicolas Roy, a younger and less expensive player. Friday, he completed a second trade, sending defenseman Colin Miller and his $3.75 million price tag, to the Buffalo Sabres and received two picks (2021 2nd round, 2022 5th round) in return.
While McPhee didn't get a roster player in return right now, he did get valuable assets which will enable him to be a buyer at the trade deadline if his team is a contender and he views the roster in need of an upgrade at a position or more.

Contracts brought in at the trade deadline are pro-rated and require less cap space. McPhee now has the assets and salary room to add a player at the deadline which he simply can't afford right now.
Miller's departure was made possible by the depth the Golden Knights have on the blueline both in Vegas and in the prospect pool. The door is now open for players such as Nic Hague, Zach Whitecloud, Jake Bischoff, Dylan Coghlan and Jimmy Schuldt to compete for jobs at the NHL level.
Vegas has a robust looking group of forwards with William Karlsson, Jonathan Marchessault, Reilly Smith, Paul Stastny, Mark Stone, Cody Eakin, Max Pacioretty and Alex Tuch filling out eight spots in the top nine. There's an opportunity for RFA Nikita Gusev and Valentin Zykov to fill an opening on the wing. And don't count out prospect Cody Glass just yet. He's hoping to come to camp and win a job. Competition for work on the fourth line will be fierce with RFA Tomas Nosek, Nicolas Roy, Will Carrier and Ryan Reaves all in the mix. Forwards Curtis McKenzie, Reid Duke and Keegan Kolesar all will get long looks at camp, as well.
On the blue line, Shea Theodore, Brayden McNabb, Nate Schmidt, Nick Holden, Jon Merrill and UFA Deryk Engelland are all slated to be in a camp as of this writing.
Expect at least one of the prospects mentioned to earn NHL work out of camp, but it could be more.
McPhee has shuffled the deck a touch but that's the natural process for a contender with a stocked development program. Some of the tall trees have to be felled in order for the saplings to have room to grow.