And with them, it is no coincidence that Boston and the Lakers have dominated the NBA in the 1980s.
Since Bird and Johnson arrived in 1979-80, either the Celtics or Lakers--or both--have been in the championship series every year. And within the next few days, one will become the first team to win four championships this decade.
"It's strange the way our careers have crossed," Bird said. "We'll probably end up building houses next to each other without realizing it."
Said Laker Mychal Thompson: "Bird and Magic are the co-kings in the NBA. I guess you can call them salt and pepper because they sure do spice up this league."
Bird and Johnson have met only 16 times in the regular season since 1979. Each has won eight games. In 1984 and 1985, they faced off in the finals. Another split.
But the basketball ledger sheet is not so perfectly balanced.
In 1979, Johnson's Michigan State team won the NCAA title, handing Bird and Indiana State their first loss that season in the championship game. In the NBA, Bird has won the Most Valuable Player award three times, Johnson one.
If one thing is certain, it's that Bird and Magic are still mentally keeping score.
"We both like to win so much that it's not hard to understand that we didn't always get along," Johnson said. "The media played a big part in creating our rivalry, but we kept it going because we both saw that we did the same things on the court. We both liked to make the great pass, rebound and score."
The dislike they felt for each other goes back to the NCAA title game. There was Johnson hugging his teammates and introducing the nation to his magic smile. There was Bird sitting on the bench and sobbing into a towel.
"I saw Magic for the first time when Michigan State played the Russians before the 1978-79 season," Bird said. "I said then that they had the best team in the country and it turned out that they beat us in the national championship game."
Johnson said: "We have a better relationship now. We used to never even speak to each other. We both wanted to win so bad that we hated each other. I respected him, but I didn't like him.
"Then we made some commercials together in '85 and we realized we had a lot in common."
Said Bird: "Hate is a strong word, but I sure wanted to beat him. But we've developed a mutual friendship with some of the things we've done together."
Added Johnson: "We found out about each other as persons. We like a lot of the same things and we're just regular guys with Midwest backgrounds. And we both like to be alone."
Although team goals are paramout to both players, their private rivalry for MVP honors took a new turn when Johnson won the award for the first time this season.
"It wasn't easy giving up the MVP to Magic, but I said early in the season that he would win it," Bird said. "He knocked out all the competition early, like Mike Tyson. There's no question he was the best player this year."
Johnson said: "He had won three MVPs and I didn't have any. I knew he respected me, but I felt I was a little below him. Now that void is gone and we're more equal."
Bird said that Johnson's increased scoring load--he led the Lakers for the first time in his career--pushed him to another level as a player this season.
"He scored a lot more points while keeping his rebounds and assists about the same," Bird said. "Teams can't play him defensively like they used to. He will score on the fast break, instead of passing all the time."
Bird's comments were illustrated in the Lakers' 126-113 victory in the championship series opener when Johnson scored 29 points with a combination of long outside shots and swooping layups. He added eight rebounds and 13 assists.
In Game 2, he had 22 points and 20 assists as the Lakers won, 141-122.
Despite his increased scoring role, Johnson realizes he won't ever be the scoring machine Bird is. At the same time, Bird won't ever match Johnson's four NBA assist titles.
"We both score, rebound and assist and we control our teams," Johnson said. "When the game's on the line, we both want the ball. But I don't try to outdo him statistically. He nearly always will outscore me."
Indeed, in Game 1, both players took 25 shots, but Bird outscored Johnson, 32-29.
Bird said the retirement of Julius Erving and the fall from prominence of the Philadelphia 76ers could serve to heighten the Bird-Magic rivalry in the future.
"In my mind, the Lakers have definitely replaced the 76ers as our biggest rivals," Bird said. "When I came into the league, our toughest games and series were always against Philadelphia. We didn't even play the Lakers in the finals until 1984, when we had been in the league for five years. Now we're meeting in the finals for the third time in four years."
Said Johnson: "Playing Larry and the Celtics is what it's all about. Playing the best is what makes the game fun."