"Bitter rivals don't make trades."

Never written in stone, this axiom nevertheless has been a common practice in pro sports for eons.

Detroit doesn't deal with Colorado. Montreal didn't deal with Quebec. The Rangers and Islanders? Nope. The Rangers and Devils. Nope again. Toronto and Detroit? Maybe in a leap year.

The Boston Bruins and New York Rangers? Phil Esposito for Brad Park?

Well here's the case of the axiom running smack dab into the immovable object. Or another familiar saying.

Necessity is the mother of invention.

After lackluster training camps and dull starts to the 1975-76 season for both teams, Rangers GM Emile "The Cat" Francis and Boston GM Harry Sinden, both of whom had coached their teams at the start of the revivals, began a game of trade-talk "Cat"-and- ... well, nobody ever took Harry Sinden for a mouse. Let's say they parried about a few ideas.

Those talks led to what many consider the most dramatic trade of the 1970s, one that positioned the two clubs for three Stanley Cup Finals appearances at the end of the decade.

On Nov. 7, 1975, the Rangers traded defenseman Brad Park, center Jean Ratelle and defenseman Joe Zanussi to the Bruins for center Phil Esposito and defenseman Carol Vadnais.

This was big. No, make that big!

In the seven previous seasons, Esposito had won the scoring title five times and twice finished second to Bobby Orr, including the previous year. Park was considered the best defenseman in the NHL next to Orr and Ratelle was one of the League's top playmaking centers. Yep, big stuff. In today's NHL, this trade is the equivalent of Detroit sending Nicklas Lidstrom and Brendan Shanahan to Colorado for Joe Sakic and Adam Foote.

"We both got off to lousy starts," Francis recalled. "In those days, Montreal, New York and Boston didn't deal with each other because we were fighting for the top spot against each other and you don't deal with your enemies.

At the time of his trade from New York to Boston, Brad Park was considered the second-best defenseman in the League to Boston superstar Bobby Orr.

"But the press really turned on us and the players. We'd had the good years, but we didn't win the Stanley Cup. We were getting older and we knew we had to shake things up.

"Eddie Giacomin had a bad knee and I tried to trade him several times. I got John Davidson that summer because I knew Eddie's time was limited and John was only 22. Every time I used him the crowd chanted, 'Eddie, Eddie'. So, I put Eddie on waivers and Detroit claimed him and who did we play next in Madison Square Garden? Detroit. It was 55 minutes of 'Eddie, Eddie' until the last five when it turned to 'Kill the Cat, Kill the Cat.' I came off the bench and I had 10 security guys surround me.

"So, I made the initial call and we were discussing this guy and that guy and I said, 'Harry, there's no point talking twos and threes. If we're going to shake these teams up, let's talk about the better players.' I said I'd talk about Brad Park. He asked who I wanted to talk about and I said Orr. This went on for about a month and I flew in there a couple of times.

"Then, about a week before the trade, we looked really bad in Philly and I put the whole team on waivers. I did. I told them I was going to do it. Then Harry asked about Ratelle and I said I needed Espo, but those names didn't come up the first three weeks."

"Both teams were going badly and we needed a change," Sinden agreed. "Some insignificant trade of bottom-line players wasn't going to cut it, so we traded our best players. The only fear I had was Park's knees. We checked it out and we watched him play. I had my chief scout watch him play in four-straight games, one in Montreal, one in Vancouver and one in New York -- and another I can't remember -- and he was the No. 1 star in each game.

"I had the same concern about Orr's knees, so we wanted Park because of that concern. I knew I couldn't give up Orr, I valued my life," Sinden said with a laugh. "So, I guess I got around to Esposito somehow. Ratelle had that broken ankle a few years earlier, but he was OK. We weren't concerned about his injury. He had played in all their games for them that year.

"The key from our standpoint was Park and the reason we went on with Ratelle and Vadnais was because they needed a defenseman and I needed a center to replace Esposito. We did that so each wouldn't have a big hole in the lineup.

"Emile ended up with one of the great centers of all time and I wound up with one of the great defensemen of all time," Sinden said. "Park was one of the top six defensemen to ever play in the NHL. Both Phil and Park went to the Hall of Fame, as did Ratelle. This was a trade of really top players. Providing injuries didn't get in the way, the deal should have worked for both teams.

"My concern was losing Orr to his injury. In Boston, we were able to see the value of a top defenseman. Orr was the top defenseman in the history of the NHL to that time and, in my opinion, still is. We were in danger of losing him. If we could get the defenseman who was second to Orr, which Park was, we could afford to give up the best scorer in the League. Emile may have had concerns about Brad's knees as I had about Orr."

Before arriving on Broadway, Esposito had won five scoring titles in the previous seven years and was among the most popular players Boston has ever known.

Francis had no qualms about Park's soundness and would have had no insight into Orr's. Park would play another 10 years while Orr had played his final effective season, although he wouldn't retire until 1979.

"Park had two knee injuries but he got over them," Francis said. "He played in the playoffs with a big brace. There was no concern about his health."

You have to wonder if Sinden wasn't trying to get a little edge on Francis by asking for the extra player, Zanussi. If so, "The Cat" was playing cute, too. He'd wanted Vadnais for years.

"They asked for Joe Zanussi," Francis continued. "He was in Providence and he wasn't going to play for the Rangers. He was a good guy. He could skate like hell and was a good team man. He had a good shot, but he was by far the smallest guy we had. He had a good year that year for them, though."

Zanussi played 60 games for Boston that year, the most in his four-year NHL career.

"But I got Vadnais," Francis crowed and the pride is still there when he tells the story. Vadnais gave the Rangers seven good years, long after Francis was gone.

Addition of Vadnais almost killed Espo deal