The Boston Celtics put their fate on the wings of Larry Bird tonight, and he lifted them to a convincing 118-99 victory over the Philadelphia 76ers at the Boston Garden to even their NBA Eastern Conference championship series at one game each.

The next two games of this best-of-seven series will be played Friday night and Sunday afternoon at the Spectrum in Philadelphia, where the Celtics have lost nine straight times. The last time they won there was Jan. 20, 1979.

Tonight belonged to Bird, the Celtics' 6-foot-9 1/2 do-everything forward.

He made 14 of 21 field-goal attempts on his way to 34 points. He also had 16 rebounds and five assists.

As impressive as Bird's numbers are, they don't reveal his true value tonight. The numbers don't show the picks he set that freed teammates for open shots, and they don't show the passes he made that led to someone else's assist.

Bird's talents are such that he makes the other Celtics play better. And tonight, the Celtic magic that wasn't there Tuesday returned.

"What Larry Bird did to us tonight, most people can't do in a season," said Philadelphia Coach Billy Cunningham. "He destroyed us."

The key to Bird's game is his outside shot. When it's on, he's on, and in this game it was. Of his 14 field goals, 11 came from 16 feet or beyond and seven were 20-footers.

"I made the mistake once after a game of saying that he (Bird) amazes me," said Boston Coach Bill Fitch. "I won't say that again, because I've come to expect these kinds of games from him. He's just a great player."

Tuesday night, Bird had 33 points and played all 48 minutes. He played the first 31 tonight before going out for a rest.

"I just try to keep moving all the time," Bird said. "Sometimes when you might start to feel tired, you reach down in yourself and say, 'Hey, I want to win this game,' and you don't get tired . . . I'm tired now, though."

The 76ers, who won the first game of the series, 105-104, appeared to be going through the motions at times tonight, content to return home with the split they wanted.

"We just showed up, but didn't come to play," Cunningham said. "Maybe we were tired, but you can't use that for an excuse. When you're tired, you're supposed to make up for it and try and wipe it out mentally. The way we played tonight, we're going to have to sit down and talk it over."

Rookie Andrew Toney was the only consistent Sixer; he had 35 points, seven rebounds and seven assists. He scored 16 of his points in the fourth period, when the game was out of reach. Toney had 26 points Tuesday and made the two free throws in the final two seconds that won the game for Philadelphia.

The next highest 76er scorer was Julius Erving with 12 points.

Substitute Kevin McHale of Boston scored 20 points, making 10 of 14 shots. Tiny Archibald had 19 points and Robert Parish 17.

The game was won in the first half.

After falling behind, 8-0, the 76ers were left to play catch-up, and with their hearts apparently not in it 100 percent, that was futile.

They made one serious run, cutting the margin to 45-41 in the middle of the second quarter after Toney, Erving and Bobby Jones rallied them. But the Celtics collected themselves and took off on a 14-0 spurt. That made the lead 18 points and the Sixers remained relatively quiet the rest of the night.

Bird, Parish and M.L. Carr had four points each in that spurt.

Adding to the Sixers' miseries was foul trouble. Both Darryl Dawkins and Caldwell Jones got three fouls early and when they were on the bench is when the Celtics ran off their 14 straight. The No. 3 Philadelphia center, Earl Cureton, looked like he had no idea what was going on or why he was out there, and that added to the Sixers ineptness.