TORONTO -- The Maple Leafs are hitting the road -- and preparing to once again play in front of fans -- minus one of their stars.

The team announced Friday that Mitch Marner and fellow winger Pierre Engvall have been placed into the NHL's COVID-19 protocol.

Toronto head coach Sheldon Keefe said both players were experiencing mild symptoms after testing positive as their teammates prepared to open a four-game road trip Saturday against the Colorado Avalanche.

"It's just the reality of the situation," Leafs defenceman Morgan Rielly said following practice before the club flew to Denver. "Everybody's going through it. We've just got to keep focused on the guys we have available.

"Next man up and get out there and work."

Marner, who missed six December games with a shoulder injury, and Engvall are the 16th and 17th players off Toronto's roster forced into isolation since the team suffered through a coronavirus outbreak last month, but the only two currently sidelined.

Leafs defenceman Timothy Liljegren rejoined the group Monday, while No. 1 centre Auston Matthews had a COVID-19 scare this week with a false positive before being cleared to play in Wednesday's 4-2 home victory over the Edmonton Oilers.

Seven staff members, including Keefe, have also gone through the league's protocol.

The Leafs returned to action New Year's Day following their outbreak with a 6-0 win over the severely undermanned Ottawa Senators before that decision against Edmonton, which was also shorthanded with three players -- including Connor McDavid -- out due to the coronavirus.

"That's the world we're living in," Toronto forward Jason Spezza said of his side's current absences. "We've kind of gotten used to it."

The Leafs have also gotten used to winning regardless of who's in or out of the lineup -- whether it's due to injury, suspension or COVID-19.

Toronto owns a league-topping 20-4-1 record and an .820 points percentage since starting the season a sluggish 2-4-1. The Leafs rank first in goals against (2.16), third in goals for (3.80), first in goal differential (41) and first on the power play (35.2 per cent) over that span.

No. 1 netminder Jack Campbell, meanwhile, has gone 15-3-1 with a NHL-best .944 save percentage and 1.73 goals-against average to go along with four shutouts.

"There was a period where we played great hockey and dominated games," said Spezza, who's in his 19th NHL season. "And I think there's times where we were getting results when we weren't playing as well.

"Those are good signs for a team."

Toronto went 17 days between games before returning to action last weekend and then again Wednesday inside a fan-less Scotiabank Arena because of provincial COVID-19 restrictions in response to the fast-spreading Omicron variant.

"We were really in a groove there, but the break ... there's obviously a significant disruption," Keefe said. "And that's where we're at now, just finding our way back to where we've had success."

Apart from Saturday's game versus the high-powered Avalanche -- Colorado is 16-3-1 since Nov. 11 with an average of five goals for per contest -- Toronto will also visit the Vegas Golden Knights, Arizona Coyotes and St. Louis Blues.

"The way that we've played in the two games since coming back from the break, that's not going to cut it on this road trip," said Keefe, whose team thumped the Avalanche 8-3 on Dec. 1. "It's certainly not going to cut on Saturday against Colorado.

"We've got to play a lot more connected, have a lot more urgency."

Spezza said the Leafs will be looking to re-establish their game, one that includes solid structure the group can fall back on in crucial moments, following a so-so performance versus Edmonton.

"It's starting to become our identity," the 38-year-old said of Toronto's sound defensive play. "I think we've changed our perception.

"We've been able to have some sustained success here for the last 25 games."

Toronto will play at least its next six contests -- the Leafs have rescheduled two home dates later this month because of those capacity restrictions -- with spectators in attendance in U.S. markets.

"When you go from having fans to playing in an empty building, it can be challenging," Rielly said. "I'm not going to lie."

"It's going to be exciting coming into these rinks with packed barns," added versatile forward Alexander Kerfoot, who skated in Marner's spot on the right side with Matthews at practice. "It shouldn't be ... but it's sometimes hard to create your own energy without the fans.

"We felt that a little bit the last couple games."

Spezza said stepping on the ice and staring at tarp-covered seats and hearing the canned crowd noise in Toronto was an adjustment after a stretch of full buildings.

"Probably harder this time because we've had fans," he said. "When we started (last season) with no fans, it almost became the norm. You forgot how it was to have fans once you got into the rhythm of things. Heading on the road here, we can definitely use the juice from the crowd.

"Even if it's as the visiting team."

Notes: Nick Ritchie, who has just one goal in 30 games, cleared waivers and looks set to play on the third line Saturday. The winger, 26, signed a two-year, US$5-million contract with the Leafs in free agency, but has been a disappointment after starting the season with Matthews and Marner. "It's not just a reflection on Nick," Keefe said before it was revealed Ritchie would be sticking around. "It's a lot to do with our situation with our team and salary cap -- decisions have to be made." ... Keefe said injured winger Ondrej Kase (undisclosed) isn't expected to play in Colorado. ... Toronto assigned forwards Joey Anderson and Brett Seney to its taxi squad.

This report by The Canadian Press was first published Jan. 7, 2022.