O'Connell's return coincided with the arrival of future 2nd overall pick Jack Eichel and the team won both the conference regular season and tournament titles. The Terriers received the #3 overall seed and marched all the way to the championship game where they couldn't overcome two third-period goals and lost to Providence 4–3. O'Connell was promoted to associate head coach the following year and the Terriers continued to produce good results, appearing in each of the next three tournaments and making the quarterfinal round twice. While the ultimate prize eluded the team head coach David Quinn accepted the same position with the New York Rangers in the spring of 2018 and less than two weeks later O'Connell was named as his successor.