 Despite leaving college hockey, Donato was still enrolled in Harvard classes and was aiming to finish the semester while playing in the NHL.He made his NHL debut the next day where he recorded his first NHL goal and added two assists in a 5–4 overtime loss to the Columbus Blue Jackets.Donato made his playoff debut during Game 2 of the 2018 Stanley Cup playoffs in a 7–3 win over the Toronto Maple Leafs.