The 25-member Londonderry High School percussion squad carried on its tradition of performing at Celtics' games with an appearance last week.
This was the sixth consecutive year for the drummers to perform at halftime during an NBA match-up.
The Lancers played four arrangements from their repertoire and performed for each side of the court.
The drumline is the heartbeat for the 310-member Lancer band and color guard.
The Celtics capped the night off by beating the Mavericks, 102-96.
For information on the Londonderry Lancer music program, visit lancermusic.org.