Born October 27, 2001, in Carbonear, NL, Mercer is currently one of the players who will represent Canada at the 2021 World Junior Championship, held in Edmonton, Alberta. Canada's tournament will commence on Day 2, December 26, against Germany at 6:00 pm EST. He is one of six returning players who won gold at the 2020 tournament, appearing in seven games.
Prior to joining Hockey Canada, he started his second year with Chicoutimi (QMJHL) serving as the club's alternate captain. In five games, Mercer had four goals and three assists for seven points for the Sagueneens. He split 2019-20 between Drummondville and Chicoutimi, finishing the season with 60 points (24g-36a) in 42 games, which ranked 12th in the league in points-per-game (1.43). For his efforts, Mercer was nominated for the Michael Bossy Trophy, which is awarded annually to a player in the QMJHL judged to be the best professional prospect (2017 Winner - Nico Hischier). In 176 QMJHL games over three-plus seasons, the right-handed center has 69 goals and 88 assists for 157 points, averaging .89 points per game.
Mercer is just the seventh player from his home province to be selected in the first-round (last: A. Newhook, 2019) and selected at 18, he is the fourth-highest pick from Newfoundland and Labrador to be drafted into the NHL. Mercer's younger brother, Riley was just drafted by Drummondville earlier this summer, and his younger sister, Jessica, plays triple-A bantam in Newfoundland.