The enigmatic Flyers have points in five straight games, so they went into the holiday break feeling pretty good about their future, especially with top-pairing defenseman Ryan Ellis on the verge of returning from an unspecified injury.

But Ellis was put on the COVID-19 protocol list Sunday, and there’s no way of knowing when he will be available. He has played just four games since being acquired from Nashville.

And then came Monday’s bombshell as three more key players – goalie Carter Hart and center/wingers Scott Laughton and Derick Brassard – were added to the COVID protocol list.

How depleted are the Flyers?

Well, Nick Seeler centered a line at Monday’s practice in Voorhees. Seeler, who was just a placeholder Monday, is a defenseman who hasn’t scored since 2018-19.

The Flyers now have seven players on the protocol list. Besides Ellis and the three players added Monday, Kevin Hayes, Sean Couturier, and Morgan Frost are also on it. Hayes and Frost may come off the list Tuesday and make the four-game West Coast trip, which starts Wednesday in Seattle.

“The good teams, the character teams, they don’t use excuses,” interim coach Mike Yeo said after Monday’s practice. “We have two days to work on our game, to continue to build habits, and to prepare for a big road trip.”

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Before the illnesses hit, the Flyers (12-12-5) had steadied themselves after an awful start that included a 10-game losing streak that got two coaches fired

What do the Flyers need to do to avoid missing the playoffs in back-to-back seasons for the first time since 1992-93 and 1993-94?

Here are five things:

1. Get the power play to wake up.

Not only has the power play failed to score much, but it hasn’t created momentum by at least getting lots of quality chances.

Overall, it is 26th in the NHL, clicking at just 15.9% — or about half of Edmonton’s rate (31.9%).

The good news: The Flyers’ power play has shown improvement since Yeo became the interim coach and handed the PP duties to assistant Darryl Williams, who took over the task from the fired Michel Therrien. The Flyers are 4-for-15 (26.7%) under the new regime.

Yes, they will gladly take that rate the rest of the season.

2. Maintain the offense that has been rediscovered under Yeo.

In seven games since Yeo replaced Alain Vigneault, the Flyers are 4-2-1 and have averaged 3.7 goals per game. Before that, they had gone 17 straight games scoring three goals or fewer, averaging 1.65 goals in that span.

The Flyers are 4-0-1 in their last five games.

“We want to carry on the momentum that we had going into the break,” Yeo said.

Players like Oskar Lindblom, James van Riemsdyk, Travis Sanheim, and Travis Konecny have had increased production since Yeo was promoted.

That needs to continue.

3. Reduce opponents’ scoring chances.

The Flyers are allowing a staggering 34.6 shots per game, the league’s second-worst figure. Six of the seven teams who have allowed the most shots — Columbus, the Flyers, Buffalo, Ottawa, Montreal, and Arizona — are out of playoff spots.

4. Take advantage of a favorable schedule.

The Flyers went through a rugged schedule in November and early December as they played mostly high-quality opponents. But the schedule eases up the rest of the way, starting with Wednesday in Seattle (10-17-3). That starts a stretch in which four of the Flyers’ next six games are against non-playoff teams. (Seattle has also been hit hard by COVID and has four defensemen in the protocol.)

After completing this four-game West Coast trip, the Flyers have just one road trip of more than two games.

5. Get healthy.

This may be No. 1 on the list.

Getting Ellis back is the biggest key, but the Flyers are now missing their four best centers (Couturier, Hayes, Brassard, and Laughton) if you categorize Claude Giroux as a left winger. That’s a lot to overcome, and the 10-game losing streak has made their predicament even more challenging.

Yeo said the call-ups from the Lehigh Valley Phantoms “are wearing a Philadelphia Flyers logo for a reason. Those who have been in Lehigh have been doing a good job and they’ve been champing at the bit to get this opportunity. Well, here it is. Take advantage of it.”

Giroux said it was exciting to have some younger players in the lineup.

“They’re motivated. They want to stay with us,” he said.

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