NEW YORK (CNN/Money) - It's been a momentous offseason for baseball, with these highlights:

• The steroid scandal, complete with congressional hearings.
• Major stars changing teams and leagues, taking some team payrolls to new heights.
• A near continuous celebration by fans of a long-suffering team, who finally won.
• The first franchise relocation in 34 years.

But perhaps the most important event for the long-term popularity of baseball took place far from any ballpark.

The tussle between owners and players in the National Hockey League may have set baseball on a course to another bruising labor war.

The NHL owners locked out the players and stayed the course even though it meant losing an entire season. After holding firm through much of the talks, the NHL Players Association eventually agreed to the concept of a cap on team payrolls in February.

Now, it seems likely that whenever the NHL does reach a labor pact, limits on team payrolls will be part of the deal.

The NHL owners' success in breaking union opposition to a cap could embolden hard-line baseball owners who have long wanted a cap of their own, according to a source familiar with the owners' position.

Before the current baseball pact expires on Dec. 19, 2006, the NBA and NFL will also go through labor negotiations. But both those leagues already have salary caps in place, and neither will disappear in the next contract.

If baseball is the last league without a cap, the salary hawks will only get louder in their demands for a limit on team payrolls.

"If NHL gets a hard cap and then comes back to less than a 20 percent drop in attendance without a several-franchises collapse, the MLB owners will be on war path," said Gary Gillette, editor of the Baseball Encyclopedia, and co-chairman of the business of baseball committee for the Society of American Baseball Research.

The best chance of baseball avoiding another nuclear labor war, Gillette thinks, is for NHL attendance to plummet.

"If the NHL has a 30 to 40 percent drop in attendance and several franchises collapse, then I think there will be a pause before the (baseball) hawks put on war paint, " he said.

As acrimonious as baseball labor negotiations have been in the past, there are some promising signs. Baseball's 2002 labor pact was the first one reached in more than 30 years without a work stoppage of some sort.

"Most hockey teams can stay out almost indefinitely because they lose less money by not playing than by playing. That's not true for baseball," said Sal Galatioto, a leading investment banker for sports teams in all leagues. "I think the majority of owners know that the value for them is keeping the gates open."

Rob Manfred, the owners' chief labor negotiations, did not respond to a request for comments on the possible impact of the NHL labor situation. But union president Donald Fehr commented recently that he doesn't think the NHL talks will affect baseball's talks.

"The economics of the sports are different, the makeup of the people is different," he said. "They all stand alone.''

But Fehr's predecessor, Marvin Miller, said that the union's agreement to open the labor contract this offseason to toughen steroids testing and penalties might raise hopes of some baseball owners that labor is not as unified as it has been in the past.

"Some of the players were leaning on leadership to do most destabilizing thing possible for a union, to open they contract," Miller told me this week. "They will rue the day they did this."

Miller believes the union will remain completely steadfast in opposition to a salary cap, even if the other three major sports unions agree to such a limit on salaries.

Steroids testing and a salary cap "are two very different things," said Miller. "Take the most right wing ballplayer -- take Curt Schilling -- ask him about a salary cap. I imagine they're no more willing to accept it now than before."

The next round of talks could find some of the owners in favor of going nuclear if they think it can get them a salary cap, and the union as opposed as ever to such a limit on salaries. That's not a good prescription for those who want to watch all 162 games of the 2007 season.

So even if you're a baseball fan who doesn't know or care the first thing about hockey, it's worth keeping an eye on the outcome of that sport's labor woes.

They could end up icing baseball before you know it.