2008-09: Played for the Huddinge Junior-18 squad. In 30 games, Boyce-Rotevall scored 4 goals and added 8 assists for 12 points. Boyce-Rotevall also played for the Stockholm 1 (Rikspucken) team, picking up 3 assists in 6 games.
2009-10: Boyce-Rotevall played for the Timra Junior-18 squad for most of the season. In 40 games, he scored 14 goals and added 24 assists for 38 points. In 5 playoff games, Boyce-Rotevall scored 2 goals and added 3 assists for 5 points. Boyce-Rotevall also played in 4 games for the Junior-20 team, picking up 1 assist. Boyce-Rotevall played for Sweden's bronze medal team at the World U-17 Hockey Challenge, scoring 1 goal and adding 2 assists for 3 points in 6 games.
2010-11: Boyce-Rotevall received his first action in Sweden's Elite League, playing in 33 games for Timra. He scored 1 goal and added 2 assists for 3 points. Boyce-Rotevall also played for Timra's Junior-20 team, playing in 31 games. He scored 15 goals and added 15 assists for 30 points. In 3 playoff games for this team, he scored 1 goal. Boyce-Rotevall played for Sweden's silver medal squad at the 2011 U-18 World Junior Championship, scoring 4 goals and adding 2 assists for 6 points in 6 games.
2011-12: Boyce-Rotevall skated in 46 of 55 games for last-place Timra in Sweden's Elitserien and was on Sweden's gold medal-winning squad at the 2012 U20 World Junior Championship. He scored 2 goals with 1 assist and was minus-two with 2 penalties, averaging just under ten minutes of ice time per game, with Timra. He played in nine of ten games during the qualifying playoffs and had one assist. Timra finished first in the sixt-team series – maintaining its spot in the Elitserien. Boyce-Rotevall was scoreless with 2 penalty minutes and was an even plus-minus in six games at the WJC. Sweden beat Russia, 1-0 in the championship final. Boyce-Rotevall was ranked 24th amongst European skaters in Central Scouting's final rankings prior to the 2012 NHL Draft.