The Philadelphia Flyers' game against the New York Rangers on Sunday is postponed with three Flyers players -- Justin Braun, Travis Sanheim and captain Claude Giroux -- on the NHL's COVID-19 protocol list.

This is the second-straight postponed game for the Flyers, though the league says that Philadelphia will be able to reopen its practice facility on Monday. The Flyers' last game was Feb. 7, and they are next scheduled to play on Feb. 18 against the Rangers.

Philadelphia also is scheduled to play in the NHL's outdoor game at Lake Tahoe on Feb. 21.

NHL chief creative officer Steve Mayer told ESPN via text that he expects all four teams scheduled for the Lake Tahoe games -- the Flyers, Boston Bruins, Colorado Avalanche and Vegas Golden Knights -- will take part in the outdoor games. But he said the NHL has teams that are ready to be swapped into the event if one or more of those teams are unable to participate because of COVID-19.

The news comes amid a rash of cases in the NHL; five teams have had to pause games this week, while the league pulled Golden Knights forward Tomas Nosek in the second period of a game Tuesday night after his test result came back positive.

League sources told ESPN that the NHL and NHLPA are discussing enhanced health and safety protocols, including genetic sequencing that will help track strains of COVID-19 and determine if the virus is transmitted during games. The NHL and NHLPA have been communicating daily and could announce the new protocols as soon as this week.

If new protocols are formalized, it would be the second time the NHL amended its health and safety procedures since the season began on Jan. 13. The NHL has had to postpone 35 games this season, with many not yet rescheduled.

ESPN's Greg Wyshynski contributed to this report.