No next-year repeats popping up among pro basketball champs

For more than a decade no National Basketball Association team has held anything but a one-year lease on the league championship. Every other major team sport has produced back-to-back champions during this period. In baseball the A's, Reds, and Yankees were all repeaters; in football, Miami and Pittsburgh won titles in consecutive years; and in hockey, Philadelphia and Montreal turned the trick.

The last time an NBA crown remained in the same hands was during the 1968-69 season, when the Boston Celtics placed ditto marks on the championship scroll. That culminated the Bill Russell era in Boston and spelled the end of the game's only real pro dynasy (the Celt, ics won 11 of 13 titles beginning with the 1956- 57 season).

Since 1970 the NBA has become highly unpredictable, perhaps owing to the delicate chemistry of a winning team and the overall balance in the league.

But while the champion's identity keeps changing, the destination of past champions does not. Three years after winning the title, most wind up with losing records, last-place finishes, or both, Sports illustrated discovered. The Lakers established the pattern, winning the league championship in 1972, then hitting bottom in their division in 1975. Others to follow suit were the 1973 New York Knicks, the 1975 Golden State Warriors, the 1976 Boston Celtics, and the 1977 Portland Trail Blazers.

True to form, the Washington Bullets (the 1977 NBA champs) are playing sub- 500 basketball, yet managing to keep out of the cellar. Seattle, however, is running ahead of schedule, stumbling along in last place with a losing record just two years after being crowned champions.