Jonathan Marchessault, Cody Eakin, Pierre-Edouard Bellemare and Tomas Tatar scored goals for Vegas, which improved to 18-3-2 in games against Pacific Division opponents and 26-9-2 at T-Mobile Arena. Malcolm Subban and Fleury combined to stop 29 shots for the Golden Knights.
Fleury, who made his 10th straight start and 21st over 22 games, left after making seven saves in the first period, one of them coming on a Brandon Sutter shot that caromed off his mask midway through the period.
The 33-year-old Fleury, who missed two months earlier in the season with a concussion, didn't return to the bench for the rest of the game. Vegas did not give an official announcement why Fleury departed the game.
Subban, making his first appearance since a 5-2 loss at Minnesota on Feb. 2 after sustaining an upper-body injury in a morning skate on Feb. 8 at San Jose, stopped 22 of the 23 shots he faced.
Jacob Markstrom had 24 saves and Sutter scored his seventh goal of the season for Vancouver.
Vegas scored two goals in the first five minutes and built a 3-0 lead in the first period.
Marchessault snapped an 11-game goal drought with his 23rd at 3:56, one-timing a shot from the slot past Markstrom's glove. Eakin followed 53 seconds later with his 10th, swatting in a long mid-air rebound of a Shea Theodore shot. Bellemare then made it 3-0 when he one-timed a pass from Tomas Nosek in the slot with 33 seconds left in the period.
Tatar, obtained in a trade with the Detroit Red Wings on Feb. 26, scored his 18th of the season but just his second with the Golden Knights when he tapped in his own rebound in the second period to make it 4-0.
Sutter scored Vancouver's first even-strength goal in five games when he fired a wrist shot through Subban's pads from the right of goal at the 8:27 mark of the third period.
--Field Level Media
|Brandon Sutter 1||Points||Pierre-Edouard Bellemare 1|
|Brandon Sutter 1||Goals||Pierre-Edouard Bellemare 1|
|Alex Biega 1||Assists||Erik Haula 1|
|N/A||Power Play Goals||N/A|
|N/A||Short Handed Goals||N/A|
|Jacob Markstrom .857||Save Percentage||Marc-Andre Fleury 1.000|
|Jacob Markstrom 24||Saves||Malcolm Subban 22|
|Team||Shots||Goals||Power Play||Penalty Kill||Penalty Mins||Face Offs Won|