[RELATED: NHL Free Agent Tracker | Fantasy impact of free agent signings]
1. Toronto's time is now
With Tavares, Auston Matthews and Nazem Kadri, the Maple Leafs have the center depth on their top three lines that is necessary to win the Stanley Cup.
What they have is at least comparable, if not arguably better than, what the Washington Capitals have with Nicklas Backstrom, Evgeny Kuznetsov and Lars Eller, and what the Pittsburgh Penguins had with Sidney Crosby, Evgeni Malkin and Nick Bonino the previous two seasons.
If we look inside the Atlantic Division, none of the other seven teams can match the Maple Leafs' center depth. The Tampa Bay Lightning and Boston Bruins, the top two teams in the division last season, were contenders to sign Tavares. That they lost out to a division rival makes it worse.
It won't be a No. 1 and No. 2 center situation in Toronto, because Tavares and Matthews are interchangeable. Early projections have Tavares centering Zach Hyman and Mitchell Marner, and Matthews with Patrick Marleau and William Nylander.
Video: John Tavares on his new deal with the Maple Leafs
2. Islanders need to regroup
Losing Tavares is a massive blow to the Islanders, but it's not all bad.
The silver lining is they have a potential replacement as No. 1 center, Mathew Barzal, the Calder Trophy winner last season who had 85 points (22 goals, 63 assists), one more than Tavares. He'll face tougher matchups without having Tavares as his cushion.
The Islanders also have the $11 million or more they were going to give Tavares available to give to other players. They gave some of it to forward Leo Komarov, who agreed to terms on a four-year contract, and forward Valtteri Filppula, who agreed to terms on a one-year contract.
They need a No. 1 goalie and to improve at defenseman. Those were needs with or without Tavares, but now they have the money to address them.
And the future got brighter at the 2018 NHL Draft last weekend, when they selected forward Oliver Wahlstrom with the No. 11 pick and defenseman Noah Dobson at No. 12. Each was considered worthy of being in the top 10.
Video: Taking a look at the New York Islanders' future
3. Four teams avoid same fate as Islanders
The Islanders had since July 1, 2017 to re-sign Tavares before he became a free agent. They didn't, and now they've lost him for nothing.
The Los Angeles Kings, Arizona Coyotes, Lightning and San Jose Sharks made sure the same thing won't happen to them. They each signed core players to long-term contract extensions that avoid free agency and begin at the 2019-20 season.
Ryan McDonagh signed a seven-year, $47.25 million contract with the Lightning, who arguably have the deepest group of left-handed defensemen with Norris Trophy-winner Victor Hedman, McDonagh and Mikhail Sergachev. Hedman is signed for seven more seasons. Sergachev, 20, has two years left on his entry-level contract.
The Kings made official their eight-year, $88 million contract with defenseman Drew Doughty, who has the highest NHL salary cap charge ($11 million) among defensemen for the 2019-20 season. Erik Karlsson could top that whenever he signs his next contract, with the Ottawa Senators or as a free agent after thsi season.
The Coyotes did the same with defenseman Oliver Ekman-Larsson, but the financial part of his contract wasn't disclosed. The Sharks also signed center Logan Couture to an eight-year contract without disclosing the money involved.
Video: Alex Tanguay on Couture, Doughty and OEL extensions
4. Stastny key addition for Golden Knights
The Vegas Golden Knights never got a chance to formally pitch their program to Tavares. They responded by landing the second-best free agent center, Paul Stastny. Terms of the contract were not disclosed.
Stastny had 53 points (16 goals, 37 assists) in 82 games last season, including 13 points (four goals, nine assists) in 19 games with the Winnipeg Jets after they acquired him in a trade.
It had to help that Stastny witnessed the impact of the Golden Knights while playing against them in the Western Conference Final last season. He said finding the right fit was most important to him.
The Golden Knights, who struggled to handle the Capitals' center depth in the Stanley Cup Final, are better down the middle with Stastny likely moving into the No. 2 spot behind William Karlsson and in front of Cody Eakin.
Erik Haula could move to the wing, potentially replacing James Neal on the second line. Neal is an unrestricted free agent and could return to Vegas. Tomas Tatar will also get a chance to play with Stastny.
Video: Paul Stastny on signing with the Golden Knights
5. Canadiens still looking for a center
The Montreal Canadiens are still in need of a top center after never getting a chance to make a pitch to Tavares and not being able to land Stastny or Ryan O'Reilly, who was traded by the Buffalo Sabres to the St. Louis Blues on Sunday.
Montreal brought back Tomas Plekanec on a one-year, $2.25 million contract, but he's not a top center on a contending team anymore. O'Reilly would have been a nice fit, but the Blues got him for forwards Patrik Berglund, Vladimir Sobotka and Tage Thompson, as well as their first-round pick in the 2019 NHL Draft and a second-round pick in 2021.
Perhaps the best option for the Canadiens is to be patient and realize if they can't get a player like Tavares or, on a lesser scale, players like Stastny or O'Reilly, there's no reason to overpay for a player who isn't nearly as good as those three.
It might be a hard thing to do in a market like Montreal, but if the Canadiens go with the long play they could be better off in a year or two, when center Jesperi Kotkaniemi, the No. 3 pick in the 2018 NHL Draft, is hopefully ready to make a significant impact.
Video: Jets make cap room in trade with Canadiens
6. Flyers fill big hole with van Riemsdyk
James van Riemsdyk should complete the Philadelphia Flyers' top-six forward group and give them something they were missing last season, a left wing to play with Nolan Patrick.
The Flyers need Patrick to be a solid No. 2 center behind Sean Couturier. Having the ability to pair him with a goal-scorer like van Riemsdyk, who has size, protects the puck well and goes to the net, has the makings of something special.
The Flyers can use Jakub Voracek on the right wing with Claude Giroux and Couturier, and either Wayne Simmonds or Travis Konecny on the right wing with Patrick and van Riemsdyk.
Video: James van Riemsdyk speaks after signing with Flyers
7. Canucks youth movement obvious with three signings
The Vancouver Canucks feel they did a service to their young, skilled players expected to be among their top six forwards this season by addressing their depth and toughness in signing three veteran players expected to be in the bottom six.
The Canucks signed forwards Jay Beagle (four years, $12 million), Antoine Roussel (four years, $12 million) and Tim Schaller (two years, $3.8 million) on Sunday. None are fun to play against and all three are proverbial glue guys.
But these signings don't address Vancouver's scoring woes. Beagle, Roussel and Schaller combined for 61 points (24 goals, 37 assists) in 234 games last season. However, the Canucks feel they will be able to get enough scoring from their top six, with rookie forwards Elias Pettersson, 19, and Adam Gaudette, 21, likely to replace Henrik Sedin and Daniel Sedin.
Pettersson, the No. 5 pick in the 2017 NHL Draft, and Gaudette are expected to be in the top six with Brock Boeser, 21, Bo Horvat, 23, and possibly Sven Baertschi, 25, who stayed in Vancouver by signing a three-year, $10.101 million contract Sunday.
They also have Jake Virtanen, 21, who is a restricted free agent, along with veteran forwards Brandon Sutter, Loui Eriksson and Sam Gagner.
8. Blues get deeper down the middle
The Blues were another team that had Tavares in their sites but had to pivot after realizing they weren't going to get him. They did by acquiring O'Reilly in the trade with Buffalo and signing Tyler Bozak to a three-year, $15 million contract.
St. Louis had to give up Berglund, Sobotka, Thompson and the two draft picks, including their first-round pick in 2019, to get O'Reilly, but they got the best player in the trade and they solidified their center depth, which was GM Doug Armstrong's plan all along.
Now the Blues have Brayden Schenn, O'Reilly, Bozak and, in all likelihood, Robert Thomas, who turns 19 on Monday, as their top four centers going into this season. Thomas could move up the lineup as the season progresses, which could push Schenn, O'Reilly or Bozak to the wing.
The Blues missed the playoffs last season, a big disappointment in St. Louis, but this revamped center depth puts them in position to be a contender again this season. It's even better for them that in the Central Division, the Jets were unable to keep Stastny and the Stars lost out on Tavares.