Middleton was the fourth-round pick, 101st overall, of the Toronto Maple Leafs in the 2016 NHL Entry Draft. He has been a product of the Avalanche since the 2020-21 season but had only played three NHL games before this season. In 10 games this season, the 26-year-old Middleton is averaging 10:31 time-on-ice and has zero points, 10 blocks, and 14 hits. He signed a two-year, $1.55 million contract extension ($775,000 AAV).
