Atlanta 107, San Diego 102

Chicago 112, Detroit 110

New Jersey 104, Houston 86

Los Angeles 126, Milwaukee 97

Golden State 115, San Antonio 112

Portland 114, Utah 112

The U.S. Olympic Committee announced yesterday that Bob Mathias, the 1952 and 1956 decathalon champ, has resigned as head of the Olympic Training Center to become executive director of the National Fitness Foundation in Indianapolis.

New Commissioner

David J. Stern, the National Basketball Association's Number Two man for the past three years, was unanimously chosen yesterday by the league's owners to succeed the retiring Larry O'Brien as NBA commissioner.

The choice of Stern came less than a week after O'Brien announced he was stepping down when his term expired February 1. It also came with the enthusiastic backing of O'Brien, who said, "I couldn't be more pleased."

"I love the people, I love the players," Stern said. "We have a very exciting non-stop game. We believe we have great players and solid owners. Our television ratings are up and our attendance is up. Our health is good."

Although Stern, who is known for his experience in marketing and television, had been considered a front-runner for the post, the haste with which he was chosen was something of a surprise.

But O'Brien, who said he wanted an insider picked, had the item placed on the agenda for a Board of Governors' meeting called to discuss the referee's strike. When he proposed Stern, the owners quickly agreed, going through the entire selection process in less than half an hour.

"We wanted an orderly transition. The perception was that he was well-trained, knowledgeable and ready to step into Commissioner O'Brien's shoes," said Richard Bloch, owner of the Phoenix Suns and chairman of the Board of Governors.

Bloch said there were no objections from the 23 owners when O'Brien recommended Stern for the job.