The 1990 playoffs series between the Boston Celtics and the New York Knicks was a highly competitive and closely contested matchup. While the Celtics were considered to have the better overall roster, the Knicks had a strong defense and were able to execute their game plan effectively. Additionally, the Celtics were dealing with several injuries and had a few key players, such as Kevin McHale and Larry Bird, who were not at their peak due to age and injuries.
In the decisive Game 5, the Knicks were able to win a close game in Boston thanks to the clutch shooting of guard John Starks and the strong defense of big man Patrick Ewing. The Celtics struggled to get their offense going, and missed several key shots down the stretch.
While it may have been surprising for the Celtics to lose the series given their talent level, the Knicks were a tough opponent and were able to execute their game plan effectively. The 1990 playoffs series is considered to be one of the great upsets in NBA history.