The NFL and its players’ union broke off talks yesterday evening, leaving dozens of veterans in danger of becoming salary-cap casualties before free agency begins a minute after midnight today.

The breakdown, though surprising, was typical of the topsy-turvy negotiations, so far: Just when things seemed darkest, they got back on track; and when it appeared a deal could be struck, talks broke down. As they did when the union called off the talks.

“The talks ended after the NFL gave us a proposal which provided a percentage of revenues for the players which would be less than they received over the last 12 years,” said Gene Upshaw, executive director of the NFL Players Association. “After suggesting we extend the waiver deadline from six o’- clock to 10 this evening, they gave us a new proposal which was worse than their prior offer. Quite naturally, we rejected that proposal and saw no need to continue meeting.”

But Harold Henderson, the NFL’s executive vice president for labor relations, said the union rejected a proposal that would have added $577 million for players in 2006 compared to 2005 and $1.5 billion in the six years of the extension. “It’s an unfortunate situation for the players, the fans, and the league,” Henderson said.

The cuts started almost immediately.

Oakland cut quarterback Kerry Collins, saving $9.2 in cap space. Center Kevin Mawae was cut by the New York Jets, although he probably would have been gone anyway because he is 35 and missed the final 10 games of last season with a triceps injury.

Other big names could go as teams try to squeeze under a salary cap of $94.5 million. If a deal had been negotiated, the cap might have been $10 million higher – in other words, allowing teams to keep some of the players.

These negotiations were by far the most difficult since the NFL and the union first agreed to free agency and a salary cap in 1992, ending years of labor unrest that included player strikes in 1982 and 1987.The contract has been extended several times since then, most of the time with ease.

Even now, the contract doesn’t expire until 2008, but this would be the last year of a salary cap – 2007 would be uncapped, which could lead to wild spending by some teams and little by others, creating a haves/have not situation similar to the one in baseball.

One reason these talks were more difficult is that the players asked for a change in the system.

Until now, they received their money primarily from television and ticket revenues. This time, they requested their share from all team revenues, including outside money generated by everything from parking fees to stadium naming rights.

That led to difficult negotiations, in part, because the teams themselves are having their own dispute over that money because of the disparity in outside income made by low-revenue teams like Buffalo and Indianapolis and high-revenue teams like Dallas, Washington, New England, and Philadelphia. Union leaders had suggested that it would be hard to reach agreement on a labor contract until the owners settled their own differences.

Both sides seemed ready to compromise yesterday, largely because of the pressure of impending free agency, which was supposed to begin last Friday. However, it was put off for three days so the sides could keep talking.

Negotiations appeared to be at a standstill last Thursday, when the owners took just 57 minutes to reject the union’s last offer. But seven hours later, the sides reversed course and started talking again.

Upshaw said he still thinks revenue sharing is the key, although Henderson said it was never discussed. Upshaw also said the players would do as well or better sticking with the current agreement.

“Under our previous cap agreement, we got just less than 60% of all of the revenues. The NFL now wants us to cut that percentage to less than 57%. Given the enormous revenue growth the NFL is experiencing, I am not about to give back gains which we have made in the past. It is clear to me that we will do much better under our current CBA in 2006 and particularly in 2007, the uncapped year,” Upshaw said.