Sam Mooibroek (Cambridge, ON) lost 8-7 to Sam Steep (Cambridge, ON) in the Final of the Ontario Junior Curling Championships, held December 27 - 30, 2018 in Ajax, Ontario. To advance to the championship game, Mooibroek won 8-2 over Aiden Poole (Chatham, ON) in the semifinals of the 2019 Ontario Junior Curling Championships in Ajax, Ontario;
 
Mooibroek finished 5-2 in the 0-team qualifying round. . In their opening game, Mooibroek lost 8-3 to Cameron Goodkey (Ottawa, ON), then responded with a 9-4 win over Connor Massey (Toronto, ON). Mooibroek won 10-3 against Ryan Hahn (Ottawa, ON), then won 8-1 against Landan Rooney (Mississauga, ON) and 8-3 against Poole. Mooibroek went on to lose 10-8 against Steep. Mooibroek responded with a 8-6 win over Joey Hart (Whitby, ON) in their final qualifying round match.
 
. For week 20 of the event schedule, Mooibroek did not improve upon their best events, remaining at th place on the World Ranking Standings with total points. Mooibroek ranks th overall on the Year-to-Date rankings with points earned so far this season.