2008-09: Friesen skated in 64 games for the Niagara IceDogs and led the team in assists in the playoffs in his second OHL season. Friesen scored 11 goals with 22 assists and was -12 with 94 PMs during the regular season. The IceDogs reached the second round of the OHL playoffs after finishing with a sub-.500 record. In 12 playoff games Friesen scored 3 goals with 7 assists and was -2 with 25 PMs.
2009-10: Friesen was the Niagara IceDogs' second-leading scorer and finished with a team-high +18 plus/minus in his third season with the club. In 60 games he scored 23 goals and led the IceDogs with 37 assists while racking up 94 PMs. The IceDogs slipped into the OHL playoffs with a losing record for the second season. In Niagara's five-game series with the Ottawa 67's Friesen scored 1 goal with 6 assists and was -5 with 8 PMs. In his second year of eligibility, Friesen was not ranked among the 210 North American skaters in Central Scouting's final rankings but was selected by the Canucks in the sixth round (172nd overall) of the 2010 NHL Draft.
2010-11: Friesen had his best offensive season in his fourth year with Niagara as the IceDogs added several high profile prospects and finished with the OHL's second-best record. He scored 26 goals with 40 assists and was +29 with 61 PMs in 60 games during the regular season. Niagara reached the third round of the OHL playoffs and Friesen was +7 and scored 2 goals with 8 assists and 19 PMs in 14 playoff games.
2011-12: Friesen returned to Niagara for a fifth season in the OHL as a 20-year-old. Playing on a loaded Ice Dogs team that finished first in the Central Division and reached the OHL finals, Friesen was Niagara's fourth-leading scorer with 26 goals and 45 assists in 62 games and led the team in penalty minutes (106). He was one of five players for the Ice Dogs with 20 or more points in the playoffs – scoring 8 goals with 14 assists in 20 games and was plus-seven with 18 penalty minutes. Friesen was named to the OHL's third all-star team and signed a three-year, entry-level contract with the Canucks in May 2012.