The win moved Washington (38-30-8) back into playoff position, as the Caps have six more regulation/overtime victories than ninth-place Buffalo. Those teams will clash on Tuesday night in the U.S. capital.
"It's going to be the biggest game of the year, for sure," Perrault said, "and we're going to be ready for it."
Here's a look at how the races in both conferences shape up entering Monday's six-game schedule:
New York Rangers (101 points) were idle Sunday, but had their lead trimmed to one point thanks to Pittsburgh's win against New Jersey. New York's three-game road trip continues Tuesday night at Minnesota.
Boston (91 points after Sunday's 3-2 win at Anaheim) picked up another huge win on the West Coast to extend its lead on Ottawa in the Northeast Division to five points. The Bruins return home to face Tampa Bay on Tuesday night.
Florida (87 points after Sunday's 3-2 shootout loss to the Islanders) managed only one point in a shootout loss to the Isles at BankAtlantic Center. The Panthers, who are now just three up on Washington atop the Southeast Division, will visit Montreal on Tuesday.
The next five:
Pittsburgh (100 points after Sunday's 5-2 win against New Jersey) received two-point nights from five different players in a rout against the Devils at Consol Energy Center. Now just one point behind the Rangers for the No. 1 seed in the East, the Penguins will host the Islanders on Tuesday.
Philadelphia (96 points) did not play Sunday. The Flyers return to action Monday night against Tampa Bay at the Wells Fargo Center (7:30 p.m. ET, NBCSN, TSN2).
New Jersey (90 points after Sunday's 5-2 loss at Pittsburgh) had no answers for the Pens' high-powered offense and came up empty in the Steel City. The Devils will try to bounce back Tuesday night against Chicago at the Prudential Center.
Ottawa (86 points) was idle Sunday. Fresh off an impressive 8-4 win against Pittsburgh on Saturday, the Sens visit Winnipeg on Monday night.
Washington (84 points after Sunday's 3-0 win against Minnesota) received a stellar effort from Braden Holtby (28 saves) and Alex Ovechkin tallied his 36th goal of the season in a victory against the Wild at the Verizon Center. Back in playoff position and just three points behind the Panthers for first place in the Southeast, the Capitals host Buffalo on Tuesday night.
On the outside looking in:
Buffalo (84 points) was off Sunday and fell back into ninth place due to Washington's win against Minnesota. The Sabres, who have won 18 of their last 28 games, head to the Verizon Center for a huge showdown against the Caps on Tuesday night.
Winnipeg (78 points) did not play Sunday. The Jets host the Senators at the MTS Centre on Monday.
St. Louis (103 points after Sunday's 4-0 win against Phoenix) is back in front in the President's Trophy race as Brian Elliott recorded his eighth shutout of the season in a victory against the Coyotes at Jobing.com Arena. The Blues, who wrapped up their seven-game road trip, return home to face Nashville on Tuesday night.
Vancouver (99 points) did not play Sunday. Vancouver, which clinched the Northwest Division on Saturday, hosts Los Angeles on Monday night (10 p.m. ET, NBCSN, TSN).
Dallas (87 points) was idle Sunday. The Stars will conclude their home-and-home series with Calgary on Monday night at Scotiabank Saddledome.
The next five:
Nashville (96 points after Sunday's 6-1 win at Chicago) continued its dominance of the Blackhawks and cruised to an impressive victory at the United Center. Now in fourth place in the West, the Predators will visit St. Louis on Tuesday.
Detroit (95 points) was off Sunday and fell into fifth place after Nashville disposed of Chicago. The Red Wings host Columbus on Monday.
Chicago (92 points after Sunday's 6-1 loss to Nashville) was blown out on home ice by the Predators in its first of five games without suspended defenseman Duncan Keith. The Blackhawks visit New Jersey on Tuesday.
Phoenix (87 points after Sunday's 4-0 loss against St. Louis) came up empty -- both in the standings and on the scoreboard -- as it was blanked by the Blues in the opener of a four-game homestand. The Coyotes will try to turn things around on Thursday against San Jose.
Los Angeles (86 points) did not play Sunday. The Kings begin a four-game road trip on Monday night at Vancouver (10 p.m. ET, NBCSN, TSN).
On the outside looking in:
San Jose (86 points) was idle Sunday. The Sharks host Colorado on Monday.
Colorado (86 points) was also off Sunday. The Avs visit San Jose on Monday night.
Calgary (83 points) did not play Sunday. The Flames conclude their home-and-home series with Dallas on Monday night at Scotiabank Saddledome.
He's only 17 but he can see the ice so well and he moves the puck and goes to the open ice all the time, so I just think he's a player that is ready to play in the NHL. I'm really looking forward to coaching someone like this.
— U.S. National Junior Team coach Ron Wilson on Auston Matthews, the projected No. 1 pick of the 2016 NHL Draft