2009-10: Mattias Janmark-Nylen played his first full season with AIK in Stockholm in Sweden's top division after joining the club mid-season from the lower division club SDE HF the previous year. He played for AIK's U20 and U18 teams – appearing in 17 games, including four playoff games, with the U20 team and playing in 34 U18 contests (including one playoff game). Janmark-Nylen scored 4 goals with 8 assists in U20 play and had 13 goals with 22 assists for AIK's U18 team.
2010-11: Janmark-Nylen skated for AIK Stockholm's U20 team, playing in 40 Super Elit league games. He scored 11 goals with 17 assists and was +9 with 34 penalty minutes. AIK finished sixth in the Super Elit league's North Division.
2011-12: Janmark-Nylen made his pro debut in Sweden's Elitserien, appearing in 18 games for AIK Stockholm, and was the team captain for the club's U20 team. He had no points and was -4 with 2 penalty minutes in limited ice time in Elitserien play. He also appeared in three playoff games with AIK with no points or penalties. In 40 games for the club's U20 team he was the team's leading scorer with 23 goals and 38 assists and was +20 with 61 penalty minutes. AIK finished fourth in the U20 standings but lost to Farjestads in a first round playoff series. Janmark-Nylen was +1 with no points and 4 penalty minutes in three playoff games. In his second year of draft eligibility, he was ranked 98th amongst European skaters in Central Scouting's final rankings but was not selected in the 2012 NHL Draft.
2012-13: Janmark-Nylen had an impressive first full season in Sweden's Elitserien, finishing as AIK's second-leading scorer behind former Yale star Broc Little. In 55 games he scored 14 goals with 17 assists and was -4 with 32 penalty minutes. AIK missed the Elitserien playoffs, finishing six points behind eighth-place Brynas for the final spot. Janmark-Nylen, in his third year of draft eligibility, was not listed among the 130 European skaters in Central Scouting's final rankings but was selected by Detroit in the third round (79th overall) of the 2013 NHL Draft.
Has both offensive upside and defensive intelligence. Not a physical player, but a skilled forechecker who can translate that into scoring opportunities. Offensively, Janmark-Nylen is adept at both scoring and distributing the puck.
Janmark-Nylen will return to AIK of the SHL in 2013-14.