As August nears its end, multiple NHL teams have some significant loose ends left to tie up. For most of those teams, those loose ends involve the restricted free agents that remain without new contracts for the 2016-17 season. The longer these players remain unsigned, the closer these teams get to having to start their season preparations without them, at least temporarily.

While there is still just under a month before NHL training camps open, the timeline to get deals done with key RFAs is even shorter than that. In just over a week, teams participating in the World Cup of Hockey will be opening their training camps. Once that happens, most of the unsigned RFAs are going from being available to continue negotiations to being unreachable.

A number of the RFAs that made World Cup teams have expressed that they will play in the tournament whether they have a contract or not and that they will not be negotiating during the World Cup. If that includes training camp, that's three weeks without being able to solidify the contract if it isn't done before the tournament. Meanwhile, NHL training camps will open before the World Cup is over.

Basically, it would be surprising if multiple RFAs don't get signed over the next week, but it's not necessarily that simple. Considering the quality of the restricted free agents still available, there are some expensive deals that need to get done and since they've already taken this long, who knows just how quickly this can get resolved.

Somehow, Johnny Gaudreau remains unsigned. USATSI

1. Calgary Flames

Of all of the unresolved restricted free agent situations, few have been more confusing than that of Johnny Gaudreau. The team managed to get a long-term deal done with their other top forward, Sean Monahan. As good as Monahan has been, though, Gaudreau has been on another level.

Over the last two years, Gaudreau has been one of the most productive players in the NHL with 142 points and he did that during his age 21 and 22 seasons. He gave the Flames some incredible value on an entry-level contract and now they should pay him like the upper-tier forward that he is.

Gaudreau is set to go into camp with Team North America for the World Cup next week. If the Flames let him get to that camp without having a contract done, they'll risk entering their own training camp without resolution with their best forward. That's not the kind of cloud a team wants hanging over its head, especially with a new coach coming in and trying to get the club off to a fresh start.

The team has the cap space to pay Gaudreau right away. A maximum eight-year extension ensures the club gets all of what will probably be all of his peak years in the league. Negotiations can be tricky, but Gaudreau has an awful lot of leverage to command a pretty sizable contract. It would not be surprising to see his cap hit exceed the $7 million range.

2. Tampa Bay Lightning

The Lightning are getting a little more leeway on their own unresolved RFA situation because it's fairly complicated at this point. After spending big earlier in the summer to retain Steven Stamkos and Alex Killorn, while also extending Victor Hedman and Andrei Vasilevskiy, the rest of Tampa's summer was going to be challenging.

The team still has to re-sign restricted free agents Nikita Kucherov and Nikita Nesterov. Kucherov is obviously the priority. He showed last year that he can lead the team's scoring attack if needed. He's also among the 25 most productive forwards in the NHL over the last two years combined and ranks 14th in goals scored over that span. He and Stamkos offer one of the best one-two punches when it comes to goal scoring in this league, as they're often on separate lines.

The problem now is that the Lightning only have about $6.6 million in cap space for next season. Both Kucherov and Nesterov are not going to fit within that space presently. The Lightning may have to trade someone away or they have to convince Kucherov to take a discounted contract even though he has a good case to become the team's second highest-paid forward behind Stamkos.

Both Kucherov and Nesterov will be playing for Russia in the World Cup. Steve Yzerman has had a great summer so far, but this is a really big issue left unchecked on his to-do list.

3. Anaheim Ducks

The Anaheim Ducks have two major hurdles left to clear before they can head into the season on (kind of) new head coach Randy Carlyle. Both Hampus Lindholm and Rickard Rakell remain unsigned heading into the season. Both will be playing for Sweden at the World Cup and both are due raises.

Lindholm become Anaheim's best defenseman. He's not necessarily the most procutive -- hovering around 30 points a season, but he plays big minutes and drives possession. Beyond Corey Perry and Ryan Getzlaf, he's one of the most important pieces of Anaheim's core right now.

Rakell, meanwhile, had a career year with 20 goals and 43 points. It was only his second full season in the league, too, suggesting he may have some big years ahead. The club can probably get away with a short-term bridge deal with Rakell, given his lighter overall body of work.

As far as Lindholm goes, however, he's a prime candidate for a long-term contract. It wouldn't be surprising to see Lindholm command something in the $5.5 to $6.5 million range in terms of cap hit. Last offseason, Dougie Hamilton signed a six-year deal that comes with a $5.75 million annual average with the Calgary Flames. Lindholm wasn't as productive as Hamilton was in his contract year, but his all-around abilities suggest he's worth at least that much. At least.

The Ducks are typically an internal cap team and are presently $9.2 million away from the ceiling. How much they're willing to spend to retain both these players without having to lose anyone else is a real question, but they're crucial to the Ducks remaining among the West's top teams.

4. Winnipeg Jets

The Jets went big when they re-upped RFA Mark Scheifele, but things haven't gotten resolved nearly as quickly with Jacob Trouba. He's another one of the players headed to the World Cup, as he'll play for Team North America and has committed to playing whether the contract is signed or not.

Only 22, Trouba has already played a significant top-four role for the Jets and should continue to. His production has dipped each year after his standout rookie season when he had 29 points in 65 games, but Trouba's all-around game keeps him in the mix as a significant contributor to the team.

The team has to be a little careful here, but the former No. 7 overall pick has been mostly living up to expectations. Since he's coming off of a season that may not have been his best, a short-term bridge deal makes sense. There's always a risk that it kills the team later, but that may end up being the best route.

Trouba's agent is Kurt Overhardt, who is a veteran of some tense RFA negotiations - most notably with Ryan Johansen and the Columbus Blue Jackets a few years back. The Trouba negotiations have been kept much quieter, though.

This is a tricky one for both sides. If Trouba is willing to bet on himself, taking the bridge and trying to force the Jets to pay big later might put him ahead financially in the long run.

5. Buffalo Sabres

One of the quieter unsigned RFAs this offseason, at least on the national scene, is Rasmus Ristolainen. He had 41 points last season while flying under the radar in Buffalo. The big Finnish defenseman has taken steps forward each season he's been in the league and was used like a No. 1 last season. The question is, does Buffalo see him as their long-term No. 1?

While Ristolainen's point production was great last year, his possession numbers were not. Coach Dan Bylsma has already said he plans to lower the number of minutes the Finnish blueliner plays to try and help maximize his abilities.

The team doesn't have the luxury of seeing if Bylsma's theory will work before having to work out a contract with Ristolainen. On top of that, the big blueliner is going to play for Finland at the World Cup. So like everyone else on this list, they're running out of runway to get this done before it interferes with the preseason.

The Sabres have plenty of cap space for next season, even though they also have to re-sign RFA Zemgus Girgensons, too. It shouldn't be a problem for the Sabres, but getting the term right on Ristolainen's next contract is important.

The team also has to consider that they're two years away from the inevitable monster contract for Jack Eichel and another big one for Sam Reinhart. Additionally, goaltender Robin Lehner will be needing a new deal after next season.

With all of that said, Ristolainen is young and the Sabres are shallower on the blue line, both at the NHL level and in their prospect system currently. He's the future. If they can get a decent rate on a longer-term deal, it's probably a risk worth taking.

Other notable RFAs who remain unsigned: Tobias Rieder (Arizona Coyotes), Valeri Nichushkin (Dallas Stars), Dmitry Orlov (Washington Capitals) and Ryan Strome (New York Islanders).