There is no question that Larry Bird is the linchpin of the defending NBA champion Boston Celtics. It also is a fact that Kevin McHale has been a major factor in building the Celtics a 2-0 lead over the Philadelphia 76ers in the best-of-seven Eastern Conference finals.

Yet, as both teams prepared for this weekend's games in Philadelphia, the Celtics' most valuable player in the playoffs might well be guard Dennis Johnson.

In Boston's 106-98 victory in Game 2 Tuesday, Johnson made eight of 15 shots and had seven assists. In the series opener, he had 15 points and eight assists.

In Boston's 12 playoff games, Johnson has averaged nearly 18 points and seven assists in 40 minutes of action, numbers not as showy as McHale's 25 points a game or stoical center Robert Parish's 15 rebounds a game.

Bird, hindered by a painful right elbow, has yet to show the form that is expected to earn him his second consecutive regular-season MVP trophy. McHale has helped make up for Bird's woes. But Johnson remains a key player for his consistent performance, particularly his outside shooting that has forced the 76ers to abandon their plan of double-teaming down low whenever possible.

And, as usual, Johnson's defense has been steady, as Philadelphia guard Andrew Toney would agree.

Known as the Boston Strangler for his previous playoff performances against the Celtics, Toney was choked off on Tuesday. Hounded by Johnson, Toney missed 14 of 17 shots.

Afterward, Johnson said that any success he had against Toney was "truly coincidental . . . I don't guard him by myself." He quickly added that his success in the playoffs was a result of "my coming up lucky a lot."

But Boston Coach K.C. Jones had other ideas.

"He has been a terror, especially in the last four games, but that includes practices, too," Jones said. "He's been a leader, our point guard, taking on the other team's tough guy on defense and scoring some big points. I don't know what the reason is but I agree with people who say, 'If it ain't broke, don't fix it.' "

A playoff MVP trophy could be Johnson's if he keeps up this pace. He won the award in 1979 when his team, the Seattle SuperSonics, defeated the Washington Bullets for the NBA title.

"I'd just like for us to win the championship first, whatever comes along after that would be fine," Johnson said. "I'm not really aware of what I'm doing personally. If the team is winning, then I'm fine and everything is okay."

After being the focal point, usually in a negative fashion, in Seattle and later in Phoenix, Johnson has adapted nicely to the relative obscurity of playing in Boston, a town that worships Bird and adores McHale.

"I'm not a shooter, I just go out and pass the ball around," Johnson said. "I do feel comfortable and confident right now, though. I think it's because I'm taking better shots, from 17 feet instead of 20 to 22. If I hit two or three shots in a row, I know that I'm gonna take the fourth. That's not only because Larry's hurt. We're not gonna live or die with his shot. Robert's out there, Kevin's out there, and so on and so forth."

Only four teams have come back to win a best-of-seven series after falling behind, 2-0. Boston has never lost a series in which it had a 2-0 lead.

"It's time for us to go to it, to turn it around," 76ers center Moses Malone said. "It's going to change, we're gonna make our move right now."

The Celtics, normally loose-lipped, are taking a low-key approach. "It wouldn't do any good to talk," McHale said. "You can scare teams like New York but not these guys."