2009-10: Linus Arnesson played for Djurgarden's U18 and U16 teams as a 15-year-old and competed for Stockholm 1 in the 2010 TV-Pucken tournament for Sweden's high school players. Playing alongside prospects like Mika Zibanejad and Pontus Aberg on the U18 team, Arnesson scored 2 goals with 6 assists in 22 games and was +26 with 14 penalty minutes. In five U16 games he scored 2 goals with 1 assist. Arnesson scored 1 goal with 2 assists in eight games as Stockholm 1 captured the gold medal in the TV-Pucken tournament.
2010-11: Arnesson appeared in nine SuperElit games for Djurgarden's U20 team while spending most of the season with the club's U18 squad and appearing in three U17 games for Sweden in international play. He was -2 with no points and 2 penalty minutes in limited time with Djurgarden U20. Arnesson scored 2 goals with 6 assists and had 12 penalty minutes in 21 games for Djurgarden U18, which captured the U18 silver medal. Arnesson scored 1 goal with 1 assist in five playoff games. In three international matches for Sweden he scored 1 goal with 1 assist and had 2 penalty minutes.
2011-12: Arnesson appeared in three Swedish Elite League games for Djurgarden, seeing limited ice time. He was the leading scorer amongst defensemen for the club's U20 team and skated for Sweden in two international tournaments. He scored 2 goals with 13 assists and was +7 with 20 penalty minutes for Djurgarden U20 and in three playoff games was +1 with 1 assist. He also played 13 games for Djurgarden's U18 team, including four playoff games, and was +3 with 4 assists. He played four games for Sweden in the 2011 U19 World Junior A Challenge tournament in Canada and was scoreless with 8 penalty minutes. Arnesson played in six games at the 2012 U18 World Junior Championship and was +3 with 4 penalty minutes for silver-medal winning Sweden.
2012-13: Arnesson suited up for Djurgarden’s men’s team in Allsvenskan (the club was relegated to the second division following the 2011-12 season). In 31 regular season games he gathered 1 assist with 8 penalty minutes and a -3 rating. He also suited up for four promotion round games with no points nor penalty minutes. Arneson played a total of 15 times for the club’s SuperElit U20 team, gathering 1 goal, 3 assists, 22 penalty minutes and a +1 rating. He played 20 U20 games for Sweden, including all six games at the 2013 World Junior Championship in Ufa, Russia, where Sweden took the silver medal. Arnesson had no points and was an even plus/minus with 6 penalty minutes. In non-championship play he collected 1 goal, 2 assists, 22 penalty minutes and a +3 rating. He played for Sweden's U18 team at the 2011 Ivan Hlinka Memorial Tournament in August and was +2 with 1 assist in five games. Arnesson was ranked 13th amongst International skaters in Central Scouting's final rankings prior to the 2013 NHL Draft.
Arnesson has truly been a defensive defenseman to date and incorporates a lot of careful, secure actions into his playing style. His skating is actually pretty smooth and he’s a heads up player who is mobile and concentrates on shutting down the opposition. Very good backwards and lateral movement and does good job of reading how much space he can afford to leave between him and oncoming opponents. Can be a tiger in his own end and uses his quick first step and sound agility to put on the heat for opponents in his own end, particularly in the corners. Although not much of an offensive defenseman, his first pass is good and he does seem to identify passing stations well.
Arnesson will play at least one more season in Sweden before coming over to North America. At the Bruins Development Camp he mentioned that he wasn’t sure when he would be coming over yet.