The New Jersey Nets, considered the weakest team in the National Basketball Association until about a month ago, have won four of their last five games including a 101-92 victory Thursday night over the Seattle Supersonics achieved with the help of 39 points by John Williamson. Last Sunday, Williamson scored 40 points, including a field goal at the finla Buzzer that gave the Nets a win over the New York Knicks.

"The acquisition of Williamson (from Indiana in late January) has given the team the confidence it needs," said New Jersey Coach Kevin Loughery. "We now know we man win the close games. We were struggling to score in the first half but in the second half we opened things up and it worked."

The Nets used a half-court press to overcome a 14-point third quarter deficit and outscored Seattle, 28-11, in the final period. The NEts tied the scored at 88 with 3:28 remaining on Kevin Porter's two foul shots and went ahead on George Johnson's two free throws 23 seconds later.

Kevin Porter had 23 points and 14 assists for the Nets while Gus Williams paced Seattle with 24 points.

In other NBA Games:

Cavaliers 119, Nuggets 87

Austin Carr and Campy Russell combined for 23 of Cleveland's 31 points in the second period to lift the Cavs to a 58-38 halftime bulge. High-scoring David Thompson was held to only 12 points as the Nuggets were held under 100 points for only the seventh time this season.

Celtics 98, Suns 95

The Celtics made three free throws in the last 32 seconds to snap the Suns' 16-game home-court winning streak. Dave Cowens converted the first of two foul shots with 32 seconds left to give the Celtics a 96-95 edge, and the Suns missed two straight field-goal attempts. Ernie DiGregorio hit two free throws after the buzzer sounded for the final margin.