The Nashville Predators selected Fabbro, a defenseman who likes to join the attack, in the first round (No. 17) of the 2016 NHL Draft. Fabbro was coming off a 14-goal, 67-point season with Penticton of the British Columbia Hockey League, when he was named the league's best defenseman.
Fabbro had played in the BCHL to preserve his NCAA eligibility. He played the next three seasons at Boston University, where he had 80 points (22 goals, 58 assists) in 112 games, as well as helping Canada finish first at the 2018 IIHF World Championship, before signing with the Predators on March 27, 2019. He made his NHL debut against the Columbus Blue Jackets four nights later and scored his first goal one week later against the Chicago Blackhawks on April 6, 2019. Fabbro had one assist during Nashville's six-game loss to the Dallas Stars in the first round of the Stanley Cup Playoffs.