1. David Perron, LW
In my opinion at least, this will go down as one of the biggest mistakes in the short history of the Vegas Golden Knights.
Letting David Perron walk in free agency was an absolute crime, especially when you consider that the front office didn’t really engage the forward’s representatives in contract talks.
Instead, they let a key offensive weapon join the St. Louis Blues and the rest is history as they say (but more on that later).
One of many gems taken from the 2017 NHL Expansion Draft, Perron was an instant hit in Vegas and he was the heartbeat of the team that made a stunning run to the Stanley Cup Final in their inaugural year.
A key weapon on the power play, Perron gave the Golden Knights a real added offensive punch and he was relied upon a lot, averaging 17:49 minutes of total ice time per game.
He finished third on the Golden Knights in points in 2017-18 with 66 points (16 goals, 50 assists) in 70 games, including 18 points on the power play.
The wing carved out new career-highs in assists (50), points (66) and power play points (18), while he also recorded 118 hits.
Furthermore, Perron was productive in the postseason with nine points (one goal, eight assists) as Vegas flirted with the Stanley Cup.
Having more than proved himself, it was expected that Perron would be signed to a new deal by the Golden Knights but, instead, he was allowed to walk in free agency where he returned to the Blues.
Of course, the Knights went on to trade for Max Pacioretty and that deal has worked out pretty well, but Perron was a vital member of the Blues team that won the Stanley Cup in 2018-19 and he would have provided the depth scoring that the Golden Knights so missed this season.
Overall, while the Vegas Golden Knights have a pretty clean resume when it comes to constructing a roster, they whiffed on the decision not to sign David Perron to a new deal given what he brought to the table for this franchise in his one year in Sin City.
He was the one that very much got away.