Bismarck High rallied to defeat Jamestown on May 18 at Tom O'Leary in WDA play.
The Demons trailed 2-1 after doubles, but won five out six matches to take the win, 6-3.
Lauryn Andre, Bismarck High's No. 1 player, remained undefeated in the West.
Bismarck High is off until they start the West Region Tournament next week.