"We were looking for the easy way," captain Bill Guerin said. "That's why we took penalties. We can't take shortcuts."
Joey MacDonald started his third consecutive game for the Islanders. Top goalie Rick DiPietro was again on the bench as the backup. MacDonald stopped 28 shots.
Hecht scored on the power play to give the Sabres a 1-0 lead 10:09 into the game. Behind the net, Hecht threw the puck off MacDonald's stick, and it deflected into the net.
Hecht was injured later in the game.
Ruff said, "it's an upper-body injury, and he'll be reevaluated tomorrow."
Buffalo scored four times in the second period to take a 5-0 lead.
The Sabres upped their lead to 2-0 when Mair put home a rebound between MacDonald's pads at 2:22.
Vanek put Buffalo ahead by three at 7:00 with a short-handed goal.
"I think after the short-handed goal, we really took control of the game," Lalime said.
Just 99 seconds later, Pominville scored off a rebound for a 4-0 lead.
Vanek scored his second of the game at 10:32 on a power play.
Kotalik connected on a slap shot while the Sabres had a two-man advantage 58 seconds into the final period.
Lalime lost his bid for his 36th career shutout when Hunter put a slap shot past him on the short side at 5:21.
MacArthur tapped in a centering pass at 9:12 for his first of the season.
Outside of an injury, Islanders coach Scott Gordon was not pulling MacDonald.
"I can tell you right now, I'm not a strong believer in pulling our goalie to change momentum," Gordon said. "I don't want them looking over their shoulder to the bench. It's a way for Joey to find a way to battle, whatever the situation."
Islanders defenseman Radek Martinek, injured during Saturday's win vs. St. Louis, did not dress. ... The Islanders chose to wear their white jerseys for the home game. Last season, they wore the whites at home twice, and split the two games.
Copyright by STATS LLC and The Associated Press
Arena: Nassau Veterans Memorial Coliseum Location: Uniondale, New York
Referees: Steve Kozari, Paul Devorski Linesmen: Michel Cormier, Darren Gibbs
Attendance: 13,523 (83.0% full)
Team Stat Comparison
Power Play Goals
Power Play Opportunities
Shots on Goal
Jochen Hecht (1)
(Power Play) Assists: Ales Kotalik, Maxim Afinogenov
Adam Mair (1)
Assists: Maxim Afinogenov, Henrik Tallinder
Thomas Vanek (2)
(Shorthanded) Assists: Daniel Paille, Craig Rivet
Jason Pominville (1)
Assists: Ales Kotalik, Teppo Numminen
Thomas Vanek (3)
(Power Play) Assists: Andrej Sekera, Jason Pominville
Ales Kotalik (1)
(Power Play) Assists: Jaroslav Spacek, Derek Roy
Trent Hunter (2)
Assist: Thomas Pock
Clarke MacArthur (1)
Assists: Daniel Paille, Jason Pominville