club. Providence Bruins (2008–2016) Cassidy joined the Providence Bruins of the AHL as an assistant coach in the 2008–09 season under head coach Rob Murray. Cassidy held this position for three years before being promoted to head coach of the team for the 2011–12 season after Murray was fired. During his first season as head coach, the club posted a 35–34–7 record, earning 77 points and failing to qualify for the playoffs. In his second season with Providence in 2012–13, the Bruins had the best record in the AHL, going 50–21–5 for 105 points, securing first place in the Atlantic Division. In the first round of the playoffs, the Bruins defeated the Hershey Bears in five games, setting up a second-round series against the Wilkes-Barre/Scranton Penguins. Providence took a commanding 3–0 lead in the best-of-seven series, however, the Penguins mounted a comeback, and won the final four games to upset the Bruins in seven games. Providence made the playoffs once again in 2013–14, finishing with a 40–25–11 record, earning 91 points and seventh place in the Eastern Conference. In the first round, the Bruins upset the second seeded Springfield Falcons in five games, before again losing to the Wilkes-Barre/Scranton Penguins in seven games in the second round. In 2014–15, Cassidy led the Bruins to their third consecutive season with 40 or more victories, as Providence earned a 41–26–9 record, getting 91 points, as the club finished in sixth place in the Eastern Conference. In the playoffs, the Bruins lost to the Hartford Wolf Pack in five games, losing the final game in overtime to be eliminated. During the 2015–16 season, Cassidy led the team to a 41–22–13 record with them finishing in fourth place in the Eastern Conference during the regular season. The team lost the Division Semifinals to Wilkes-Barre/Scranton Penguins in three games. Boston Bruins (2016–2022) On May 24, 2016, Cassidy joined the Boston Bruins as assistant coach for the 2016–17 season. On February 7, 2017, he was named interim head coach after head coach Claude Julien was fired, and on April 26, the Bruins named him the new head coach. In his first full year as Bruins head coach, he led the team to a 50–20–12 regular season record, collecting 112 points and securing the second seed in the Atlantic Division. In the playoffs, his team defeated their rivals, the Toronto Maple Leafs, 4–3 and advanced to the