Ostapchuk was returned to AHL Belleville on Friday.
Ostapchuk made his NHL debut Mar. 12 against Pittsburgh and ended up playing five more games with the Senators before his demotion. He failed to register a point over that stretch, but he did have five shots on net while averaging 10:25 of ice time. The 20-year-old had 13 goals and 22 points in 56 AHL games before his promotion.