Philadelphia rookie Andrew Toney made two free throws with two seconds remaining tonight to give the 76ers a heartstopping 105-104 victory over the Boston Celtics in the first game of their best-of-seven NBA Eastern Conference championship series.

There is no love lost between these two teams, which tied for the league's best record in the regular season at 62-20.

Tonight, however, the 76ers showed more weapons and more poise when the game was on the line.

The Celtics made up a 10-point deficit in the final six minutes to bring the game down to the wire in what was undoubtedly one of the most hard-fought and finely played playoff contests in recent years.

Boston's Gerald Henderson made only the first of two free throws to give the Celtics a 102-101 lead with 27 seconds to play. Toney missed a jumper at the other end for Philadelphia, but Larry Bird fouled Julius Erving as Erving went up for rebound.

Erving made both free throws with 13 seconds left to regain the lead for the 76ers, 103-102.

The excitement was only starting, however.

With four seconds left, Tiny Archibald drove to the basket and then laid the ball off to Bird, who was fouled by Lionel Hollins before he could shoot.

Bird made both his free throws and the lead went back to the Celtics, 104-103.

The 76ers called time to get the ball at midcourt. Erving set a screen along the baseline for Toney and Toney broke to the left corner to receive a long inbound pass from Bobby Jones. Toney then drove by Henderson and was fouled by Cedric Maxwell on his way to the basket with two seconds to play.

"I thought I could slide over and stop him, but I struck my leg out and fouled him," said Maxwell. "It was probably the worst play I've made since I came into the NBA."

With screaming Celtic fans waving their arms and anything they had in their hands at Toney, he sank both free throws.

"To see someone stand up there on the line and hit two free throws like that does not make for very happy pillow talk," said Bost Coach Bill Fitch. t

The Celtics' last chance to win went flying as Bird's long, forced jumper hit the side of the glass as the game ended.

Toney, 6-foot-3 and the Sixers' No. 1 draft choice out of Southwest Louisiana, led his team with 26 points and Erving had 25.

Bird was high for the Celtics with 33.

Toney made his presence felt long before the final two seconds. He scored 11 of his points in the fourth quarter and had one phenomenal stretch midway throught the quarter in which he led the 76ers on a 19-4 scoring binge that turned an 83-78 deficit into a 97-87 advantage.

Toney had seven points in the spurt -- including a 28-foot three-point shot -- three assists and made the pass that led to two free throws by Bobby Jones.

Toney was too quick for Chris Ford or M.L. Carr to guard, so Boston Coach Bill Fitch went to Henderson, who did the best of the three but was still no match for the young 76er, who usually made one quick move to the basket to get his man off balance and then pulled up for the jump shot.

The Sixers were on top, 100-91, with 4:13 remaining when Cunninham inexplicably replaced Toney with Lionel Hollins. Hollins missed one shot and had another blocked as the Celtics ran off a 10-1 spurt to tie the game at 101 with 51 seconds to play.

Maxwell had four of those points, coming off offensive rebounds, and Bird matched his four.

Toney was quickly ushered back in time to win the game.

Toney was a starter most of the season before being replaced by Hollins the last month. In the final game of the Milwaukee series, he played only two minutes and failed to score.

Sitting, obviously, didn't bother him.

"I've got confidence in my game and Billy had confidence in me tonight. I'm not at all surprised they were calling my play so often," said Toney.

"He played a tremendous game," gushed Cunningham. "He was the hero in the clutch and that's what I love about him."

The Sixers didn't show any effects from their grueling seven-game series with Milwaukee that ended Sunday. The Celtics, however, seemed to have lost a little of their sharpness from their nine-day layoff after easily winning their last series, with Chicago.

All the 76ers were hoping for in these two games at Boston Garden was a split. Now they want more. They'll get their chance in the second game of the series Wednesday night.