NEW YORK — Before these NHL playoffs began, the Lightning held a team dinner, where several players spoke.When it was veteran wing Brenden Morrow's turn, his message was simple. After reaching the Stanley Cup final as a rookie in 1999-2000, Morrow, 36, hasn't been back since. "Don't have any regrets," he said. "Opportunities are few and far between."You think you'll get there every year, Morrow said, but you won't. Hockey's holy grail, the Stanley Cup, can be like a mirage in the desert, vanishing before your very eyes. In a world in which teams operate with a salary cap, the window for them to get this far is smaller than it has ever been.That makes tonight's Game 7 of the Eastern Conference final against the Rangers at Madison Square Garden arguably the most important game for the Lightning since it hoisted the Cup in June 2004."Hopefully, they understand this might be a once-in-a-lifetime opportunity," said Dave Andreychuk, the Cup team's captain. "It's not (a reality) that should be just passed by. It has to be brought up and has to be taken seriously."Sure, the Lightning is a young, talented team that should be competitive for several years. Coach Jon Cooper is a rising star. The franchise cornerstones are captain Steven Stamkos and defenseman Victor Hedman. And the Lightning has the league's most dangerous line, the "Triplets:" center Tyler Johnson and wings Ondrej Palat and Nikita Kucherov.But that doesn't guarantee anything. Only two teams have gone to back-to-back Cup finals since the salary cap was instituted in 2005-06 (Pittsburgh and Detroit in 2008-09). Plus, how long can the band stay together? Stamkos' contract is up after next season; he could sign a long-term extension in the range of $9 million to $10 million a year this summer. Hedman, who has emerged as one of the league's top defensemen, needs a new deal in two years, as do Johnson and Palat. Kucherov is a restricted free agent next summer. And the cap is expected to increase from $69 million to only $71 million next season. "The storm is coming," Morrow said.That's why the time for the Lightning to strike is now."You look at how many teams in last year's playoffs didn't make this year's playoffs," Lightning general manager Steve Yzerman said, citing the defending Cup champion Kings and the Bruins. "So you take advantage while you can. This league changes quickly."• • •Andreychuk said his Cup team is "living proof" of how fast things change.That team also had several young stars at forward, including Marty St. Louis, Brad Richards and Vinny Lecavalier. It had core defensemen in Dan Boyle and Pavel Kubina, and a true No. 1 goalie, Nikolai Khabibulin.But with the league's collective bargaining agreement expiring after that season, then-general manager Jay Feaster didn't know how the "new world" would look after those negotiations."Certainly, we all saw the cliff approaching," Feaster said. "That's why (then-coach John Tortorella) told the team before the playoffs started, 'You got here, now you might as well win this (darn) thing. Let's get this one.' "The Lightning outlasted the Flames in a thrilling seven-game Cup final for its first Cup win. But the Lightning hasn't made the Cup final since. And only two players from that team have won the Cup again: Ruslan Fedotenko with the Penguins in 2009 and Cory Stillman with the Hurricanes in 2006. "There is a window that you've got to take advantage of," Andreychuk said. "Because, eventually, you're not going to be able to sign everybody, especially if you win, because everyone is going to want to get paid, which is totally understandable."Feaster, now the Lightning's executive directory of community hockey development, said most of the 2004 team was set to come back the next season. But, after the owners locked out the players during the labor negotiations and the season was canceled, the new collective bargaining agreement kicked in."All our careful planning we had done was washed right down the sewer," Feaster said. "It changed everything."The Lightning lost Khabibulin to free agency before the 2005-06 season. Kubina left for the Maple Leafs in free agency in 2006. Richards and Boyle were traded in 2008."It's a whole lot easier to stomach when you're looking at those kinds of decisions with a Stanley Cup ring on your finger," said Feaster, who resigned as GM in 2008. "Because of the way the (labor deal) is now … when you have two teams playing a Game 7 … you want to seize the moment."• • •Nobody has to tell Stamkos about seizing the moment. The last time the Lightning got this far, in 2011, Stamkos broke his nose in Game 7 of the conference final against the Bruins when he took a shot off his face. He returned to the game a few minutes later wearing a protective cage. The Lightning lost 1-0 to the eventual Cup champions.Stamkos said Thursday that loss is more painful, and memorable, than the impact of the shot, especially after it took the Lightning three years to reach the playoffs again. Stamkos and Hedman are the only players remaining from that 2011 run. "It's just a different feel this time around," Stamkos said. "For us, you just never know where hockey is going to take you next. I was one game away, but you think you're going to be right back there the next year. It's taken four years to get back. You have to realize the magnitude of the game and situation that you're in, and really how close you are. I think our group realizes that."