The National Hockey League has fined the Montreal Canadiens and Washington Capitals $25,000 US each for unsportsmanlike conduct during warmup before Game 4, marking another round of discipline in the testy first-round Stanley Cup playoff series.

The league also announced Monday that Montreal's Arber Xhekaj was fined $3,385.42 and fellow defenceman Dylan McIlrath of Washington $2,018.23, both the maximum allowable under the collective bargaining agreement between the NHL and the NHL Players' Association, for their actions in Sunday's incident.

The league did not elaborate on why the fines were levied, but Capitals head coach Spencer Carbery said after Friday's Game 3 in Montreal the NHL had warned both teams about engaging in unsportsmanlike conduct.

The Capitals won Sunday's game 5-2 to take a 3-1 lead in the best-of-seven first-round series back to Washington for Game 5 on Wednesday at 7 p.m. ET.

It's the second round of fines issued in the series, after Washington's Tom Wilson and Montreal's Josh Anderson were each docked $5,000 for their roles in a bench-clearing altercation in Game 3.

The league appears to be trying to crack down on displays of gamesmanship in these playoffs.

• The league fined the Senators $25,000 and Ottawa forward Nick Cousins $2,083.33 after Cousins shot a puck at Toronto goaltender Anthony Stolarz in the pre-game warmup of Game 3 of their series on Thursday.
• The Winnipeg Jets and St. Louis Blues both received a warning from the league after Blues goaltender Joel Hofer and Jets forward Mark Scheifele attempted to outwait each other to be the last off the ice Friday in their Game 3 warmup.