Five takeaways from conclusion of 4 Nations Face-Off round robin

1. The NHL gets its ultimate wish — two entries in the USA-Canada rivalry.

It doesn't really matter how they got there — it was always going to be about trying to get two games between Team USA and Team Canada. In a tournament that felt designed to reward the tougher, harder style of North American hockey, this was always at the top of the NHL's wish list. 

The first game between these nations in the round robin, a 3-1 USA win on a Saturday night in prime time, peaked at more than five million viewers — making it the most watched non-Stanley Cup hockey telecast in nearly six years.

2. The second guessing has begun. 

The tournament's championship hasn't been played, but questions about roster builds are emerging. Team USA's unique blend of skill, grit and size in international best-on-best play using NHL rules — rather than IIHF rules — may change how future teams are built. It also means that future editions of 4 Nations Face-Off will hold a unique place against less physical international hockey tournaments. 

On the ice, Canada has arguably assembled the most talented forward group — with a smattering of grit down the lineup. Do they have enough to counter the Americans?

3. Injuries are the one thing that could derail the long-term viability of this tournament — they're mounting. 

It's a story worth monitoring — just who is going to play Thursday? Team USA was down to 10 forwards while already playing without Matthew Tkachuk in their loss to Sweden.

NHL GMs are mostly former players. They understand the pride players have in wearing their nation's colors. Many also understand the uniqueness of this particular tournament due to its place as the NHL's return to best-on-best hockey.

When this tournament is no longer a novelty, will the injuries that piled up cause friction with NHL front offices? 

4. The flu is now a major storyline.

The flu has made its way through the 4 Nations Face-Off teams. Canada missed Cale Makar for two games of the round robin. Sweden lost goaltender Filip Gustavsson mid-game against Finland and were without Mika Zibanejad and Rickard Rakell on Monday. 

This could have a significant impact on Thursday's championship in Boston. We'll all be waiting with baited breath to see if illness continues to work its way through the locker rooms.

5. Now that two teams are eliminated, what's next? 

You'll hear an occasional note on what constitutes "true" best-on-best international hockey. The 2016 World Cup of Hockey featured a few odd gimmicks that often result in an asterisk being placed next to it when the term best-on-best is discussed.

Likewise, there are questions about whether or not this tournament is a true best-on-best. This tournament is missing one of the best players in the world in German-born Leon Draisaitl. The German team didn't have enough active NHL players to make up a full roster. 

In the future, could certain requirements change? 

NHL players resume practicing Tuesday with their teams. Twenty-eight teams will resume game action Saturday, Feb. 22.