James Harden, who has played for the Houston Rockets less than three months, already holds an impressive franchise record, a streak of 14 games with at least 25 points.

The streak is over. The Celtics, called “old, tired and slow” by their coach last week, took a little shine off Harden’s run, keeping him just 1 point from making it 15 games with their 103-91 victory at TD Garden Friday night.