The NHL's plan appears robust and detailed.

Once players enter so-called “bubbles” in two hub cities later this month as part of the league's blueprint to resuscitate its pandemic-halted season, teams should - at least in theory - be fairly well-protected from the threat of COVID-19.

A 28-page document released earlier this week outlines a grocery list of health and safety measures where no stones seem left unturned, including mandatory daily testing and the wearing of masks whenever possible, all the way down to banning high-fives and advising against talking in elevators.

Getting to the bubbles largely unscathed by the coronavirus, however, could be the biggest challenge of all.

There will be strict rules once the 24 clubs set to compete in the league's return-to-play plan head to the hubs and are quarantined from the general public - Toronto and Edmonton are the expected destinations - but players will be free to come and go as they please during training camps slated to begin early next week.

And while the league touched on the need to be prudent with regards to physical distancing outside team activities during camps in a separate document, it's potentially a soft underbelly players, coaches and executives know could pose a risk.

“The rink is the safe spot, it's clean,” Calgary Flames general manager Brad Treliving said. “You've got the protocol that really is enforceable.

“The recommendation and the messaging to the players is going to be, 'You've got to keep that (personal circle) as tight as you can.”'

The NHL plans to test players every 48 hours during camps, and Penguins head coach Mike Sullivan said there have already been conversations amongst his group about the possible pitfalls of the next 2 1/2 weeks as the league looks to kickstart a campaign that was suspended in March as the coronavirus swept across North America.

“Exercise common sense,” Sullivan said. “It's to everyone's benefit, whether it be our players or the public in general.”

Dr. Isaac Bogoch, an infectious disease specialist at Toronto General Hospital, said that message will be crucial for the league during this upcoming period of vulnerability.

“You're not in a bubble, and players, just like everyone else in the world, are susceptible to this infection,” he said. “People have to be very careful to avoid going out and mingling with others in the world around them.”

While the virus is relatively under control in Canada, the explosion of cases south of the border, including hot spots like Florida, Texas and Arizona, represent a red flag. Of the 24 franchises tabbed for the restart, 18 are located in the United States and won't head north until the end of the month.

“I'm not going to put words in anyone's mouth,” Bogoch added. “But you can be sure teams will be reading the riot act to their players on the importance of ensuring they stay safe and healthy.”

Canucks defenceman Quinn Hughes has been holed up in a Vancouver hotel since arriving back in Canada from the U.S. in late June as part of the cohort quarantine plan approved by health officials. He's able to skate with a few teammates, but has otherwise mostly been confined to his room and is looking forward to a level of freedom.

“At a certain point we're going to have to live our lives and we're going to have to go to the restaurants and do these things,” he said. “But I think you can be calculated and smart staying away from people and doing the best you can wearing a mask and washing your hands.”

And although British Columbia has been commended for its response and control of the virus, risks remain just like anywhere else.

“It's on the players,” Hughes added. “The players have to be responsible.”

Montreal Canadiens head coach Claude Julien, who's 60 years old and in a high-risk age group for COVID-19, said his team will do whatever it can to assist players during camp, including getting groceries delivered.

“They're taking this very seriously,” he said. “They know the danger of it for them, for their teammates, for their families.

“We all have to do our jobs as far as being diligent.”

Of the 396 NHLers tested at team facilities between June 8 and Monday during small, voluntary workouts as part of Phase 2 protocols, 23 results - in the neighbourhood of six per cent - came back positive. The league said it's also aware of 12 other positive tests for players not taking part in Phase 2.

Phase 3, which represents the start of camps, will see roughly 750 players report to team facilities next week, as long as the NHL's return-to-play protocol and extension to the collective bargaining agreement are approved in the coming days.

That means nearly half of players set to compete had yet to be tested by the league as of earlier this week.

An outbreak within a team or teams could wreak havoc on the league's return-to-play plans. Major League Soccer, which started its summer tournament this week, has seen both FC Dallas and Nashville SC pull out due to 20 combined cases of COVID-19.

Bogoch, who commended the NHL for its attention to detail inside what should be tightly-controlled bubbles, said even if every precaution is taken during camps, there's a chance the virus will find a way through.

“You're relying on people's good judgment,” he said. “That might work out the vast majority of time, but it might not work out 100 per cent of the time.

“One case can certainly beget more cases.”

Exactly what the NHL is hoping to avoid.

This report by The Canadian Press was first published July 8, 2020.