"This wasn't our best game," the New York coach said he told his players. "We're going to need our best game and we're going to have to earn the right to keep playing now. I've been with this group a long time and I know the character of this group, and we'll be ready."
Following the most lopsided loss in the Stanley Cup Playoffs in their history, the Islanders have no choice.
New York must regroup quickly and win Game 6 of the best-of-7 series at Nassau Coliseum on Wednesday to force Game 7 back in Tampa on Friday. Otherwise, the Islanders' season and dream of reaching the Stanley Cup Final for the first time since 1984 will be over.
"A loss is a loss at this time of year whether it was in double overtime or the way it went tonight," New York forward Kyle Palmieri said. "We'll wake up tomorrow down 3-2, headed home with our backs against the wall. But we've got a chance to win a game at home. That's all we're focused on now."
RELATED: [Complete Islanders vs. Lightning series coverage]
The Islanders did almost nothing right from the opening face-off. The Lightning took advantage, generating numerous odd-man rushes and scoring chances off turnovers.
As a result, New York surpassed its previous largest margin of defeat in the playoffs of six goals, which happened three times, most recently in an 8-2 loss to Tampa Bay in Game 1 of the Eastern Conference Final last season.
To make matters worse, the Islanders lost center Mathew Barzal for the third period when he received a five-minute major and a game misconduct for cross-checking Lightning defenseman Jan Rutta shortly after the end of the second period.
Trotz said, to his knowledge, the Islanders hadn't heard from the NHL Department of Player Safety about whether Barzal might face supplemental discipline. If Barzal is suspended for Game 6, it would be a significant blow to New York's chances of forcing Game 7. The center has scored six goals in the past nine games.
"I'm disappointed because it wasn't going well and you just sort of dug it a little deeper for the guys," Trotz said of Barzal's major penalty.
Steven Stamkos' goal that gave the Lightning a 1-0 lead 45 seconds into the game was the sign of many bad things to come for the Islanders. By the end of the first period, goalie Semyon Varlamov (three goals on 16 shots) had been replaced by rookie Ilya Sorokin, and New York trailed 3-0.
After a brief push at the start of the second period, when Brock Nelson and Josh Bailey had good scoring chances, the Islanders lost their discipline and gave the Lightning four consecutive power plays. Stamkos (5:42) and Alex Killorn (17:53) made them pay by scoring power-play goals, sandwiched around Ondrej Palat's even-strength deflection goal (15:43), to increase the Lightning's lead to 6-0 by the end of the second.