The Celtics–Knicks rivalry is a National Basketball Association (NBA) rivalry between the Boston Celtics and the New York Knicks. The Celtics and Knicks are two of only three remaining charter franchises (the other being the Golden State Warriors) from the Basketball Association of America, which began operations in 1946. The Celtics and Knicks were both established in 1946 as charter franchises of the Basketball Association of America, and are the two oldest teams still playing in their original city today.