2009-10: Anthony Duclair was a dominant scorer in Quebec bantam hockey, finishing with 81 goals and 47 assists in 59 games for the Basses Laurentides Conquerants.
2010-11: Duclair had an impressive rookie season for Lac St-Louis in Quebec midget AAA hockey as the Lions won the provincial title and captured a bronze medal at the 2011 Telus Cup. Duclair led Lac St-Louis with 25 goals and had 32 assists in 34 games to finish second in points – one point behind Jonathan Drouin (58). Duclair added 9 goals with 14 assists in 14 playoff games. In the Telus Cup the Lions lost in double overtime to the eventual champion Winnipeg Thrashers in the semifinals before defeating Vancouver for the bronze medal. Duclair scored 5 goals with 7 assists and had 8 penalty minutes in seven Telus Cup games. He also represented Quebec in the 2011 Canada Winter Games and U17 World Hockey Challenge tournaments. He scored 1 goal with 8 assists in six CWG games and had 4 assists and 4 penalty minutes at the WHC. He was selected by the Quebec Remparts in the third round (41st overall) of the 2011 QMJHL Entry Draft and by Dubuque in the second round (18th overall) of the USHL Entry Draft.
2011-12: Originally intent on playing college hockey in the USA, Duclair instead joined the QMJHL's Remparts as a 16-year-old and was fourth amongst rookies with 66 points. Playing on a high-flying Quebec team that scored the third-most goals in the QMJHL he was the team's third leading scorer with 31 goals and 35 assists in 63 games and was +38 with 50 penalty minutes. The Remparts were third in the East Division and reached the second round in the playoffs. Duclair scored 3 goals with 5 assists and was -5 with 8 penalty minutes in 11 playoff games. He skated in his second World Hockey Challenge tournament with Canada Quebec and had 1 assist with 8 penalty minutes in four games.
2012-13: Duclair had an up-and-down season in his second year with the Remparts after skating for Canada's gold medal team at the 2012 Ivan Hlinka Memorial U18 tournament in August. He had a hat trick in his first game of the year but then missed nearly five weeks due to an ankle injury. He endured a one game team "suspension" along with teammate Adam Erne in January (both were reinstated before the next game) but rebounded to finish as Quebec's fourth-leading scorer. Duclair scored 20 goals with 30 assists and was +23 with 22 penalty minutes in 55 games. Quebec finished third in the East Division and reached the second round in the playoffs. Duclair scored 3 goals with 5 assists and finished with an even plus/minus with 12 penalty minutes in 11 playoff games. In five games at the Ivan Hlinka Tournament he scored 1 goal with 1 assist and had 8 penalty minutes. Duclair was ranked 57th amongst North American skaters in Central Scouting's final rankings prior to the 2013 NHL Draft.
A speedy sniper, Duclair relies on his great skating ability to create chances and has dynamic offensive talent to make the most of the opportunity. With the ability to make plays at top speed and sizzling acceleration, Duclair often only needs the slimmest of openings before he's on the attack. More of a shoot-first player, Duclair's shot is extremely accurate, but he needs to be more consistent. Furthermore, he would be well served to round out his game and add significant strength.