LAS VEGAS (AP) - In a game that included William Karlsson's natural hat trick and Marc-Andre Fleury getting his 48th career shutout and 401st win, Vegas coach Gerard Gallant credited a hit by forward Ryan Reaves as the biggest play.
Barely two minutes into the second period, Reaves - acquired from Pittsburgh on Feb. 23 - flattened TJ Brodie with a blast that sidelined Calgary's defenseman the remainder of the game while sparking the Golden Knights' recent stagnant offense.
''That was the difference,'' Gallant said of Vegas' 4-0 win over the Flames on Sunday. ''That changed the game around. It was a big, clean hit. Ryan's been here for 10, 11, 12 games with us right now and he's doing a good job, he's playing his role real good and that hit changed the game around for sure.''
Colin Miller also scored as Vegas snapped a four-game home losing streak and improved to 25-9-2 at T Mobile Arena. In splitting its last four games, the Golden Knights had been outscored 15-10 and hadn't scored more than three goals in a game since a 4-0 win at Detroit on March 8.
''We weren't happy with the way we played over the last couple of weeks,'' Gallant said. ''We had some real good games in there, we had some games where I thought we played OK and lost. Tonight I thought we had a tough first period and we played real good to battle back and win an important game.''
Fleury, who made his 20th start in 21 games, stopped 42 shots for his fourth shutout of the season, He also moved into a tie with Chris Osgood for 12th on the NHL's career wins list.
''I thought we played well in our zone and came out as a group together and created that way as a team going down on the other side,'' Fleury said. ''I could see most pucks, and that makes a big difference and when there (were) rebounds, they took their guys away. It's the little things that makes a big difference in a game.''
Vegas improved to 3-0-0 against Calgary while outscoring the Flames 15-5. The teams meet once more, in the regular-season finale at Calgary on April 7.
Mike Smith stopped 27 shots as the Flames, one of the league's better road teams this season, dropped to 20-11-6 away from home.
''That team we're playing there, they can score,'' Calgary coach Glen Gulutzan said. ''They got some juice from a mistake and they got their juice started with the power play. We just couldn't put one past them - especially early.''
The Flames outshot the Golden Knights, 20-6, in the first period. But with the game scoreless early in the second, Brodie looked to clear the puck as he came from behind the net when Reaves leveled him and sent the 18,075 fans in attendance into a frenzy.
''I hope it got a little energy into the boys,'' Reaves said. ''But big goals at big times, we needed to get the first one. We've been struggling to get the first goals the last couple of games, so getting the first one is even bigger. ... The last two games we've come out in the first period kind of lazy and waiting for the game to go, we did it again today. That's when I go and try and find a spark, whether it's a hit or a fight, or just getting in somebody's face, that's what I try and bring to the team.''
Not too long after Reaves' thunderous hit, and with Vegas on the power play, Miller found the back of the net with a vicious slap shot from the point 5 1/2 minutes into the period. Vegas has scored at least one power-play goal in 18 of its last 27 games.
Less than one minute later, James Neal made a steal at the blue line, created space in Calgary's zone and fed a streaking Karlsson, who one-timed it to give Vegas a 2-0 lead.
Karlsson's second goal came after he set up near the left circle, took Jonathan Marchessault's pass from behind the net, and fired a shot that deflected off Smith's glove with just under seven minutes left in the middle period.
The 26-year-old center completed his natural hat trick when he took a pass from defenseman Nate Schmidt in Vegas' zone, skated the length of the ice and lifted a wrist shot over Smith's blocker to make it 4-0 with 5:11 remaining in the second.
''I just got the chances and managed to bury them, turned out to score three goals,'' Karlsson said. ''We had that hit by Reavo, kind of got the momentum swing for us and I think we played great hockey after that. Those little things that can make a huge difference.''
Karlsson moved to the top of the NHL list of Swedish players with 62 points this season. Karlsson's 39 goals bring him closer to tying Henrik Zetterberg's single-season mark for a Swedish-born player, with 43.
NOTES: Calgary's Matt Stajan is now two games shy of 1,000 for his career. ... Vegas' Pierre-Edouard Bellemare played in his 300th career game. ... Gallant is two wins away from his 200th.
Calgary: Visits the Arizona Coyotes on Monday.
Vegas: Hosts the Vancouver Canucks on Tuesday.
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