2008-09: Magnus Hellberg played in two games for Arlanda Wings in the Swedish third league (Division 1) and was the starter for Arlanda's U18 team. He had a 3.52 GAA and .844 in 119 minutes of action for the Wings. He played 33 games for the U18 team and had 2 shutouts with a 3.12 GAA and .900 save percentage.
2009-10: Hellberg made one appearance at the pro level, allowing 3 goals in 24 minutes of action for IF Vallentuna (Division 1), and skated in 22 of 26 regular season games for Almtuna's U20 team. Almtuna finished third in their division in the SuperElit league and Hellberg finished with 2 shutouts with a 1.97 GAA and .929 save percentage.
2010-11: Hellberg skated in 31 games for Almtuna in Sweden's Allsvenskan (second league) in his first pro season, sharing the team's goaltending chores with Atlanta Thrashers' prospect Fredrik Petterson-Wentzel. Hellberg was one of the league's top goalies, recording 5 shutouts with a 2.04 GAA and .936 save percentage. He played in five of six elevation playoff games for Almtuna and was 0-5 with one overtime loss with a 3.24 GAA and .908 save percentage. Hellberg was ranked second amongst European goalies in Central Scouting's final rankings and drafted as 20-year-old by the Nashville Predators in the second round (38th overall) of the 2011 NHL Draft.
2011-12: Hellberg appeared in 17 games as a backup to Frolunda's Frederik Andersen (Anaheim) in his first season in Sweden's Elitserien and appeared in three games (including two playoff games) on loan to Orebro in Allsvenskan. He had two shutouts with a 2.60 goals against and .904 save percentage for fifth-place Frolunda. He did not see any playoff action as Andersen played all six games. Hellberg allowed two goals in an overtime win in his only regular season game with Orebro. Orebro competed in the Kval series after finishing first in Allsvenskan. Hellberg started the first two games. a 3-2 loss to Leksands and a 5-1 loss to Rogle, finishing with a 4.04 goals against and .884 save percentage. He signed a three-year entry-level contract with Nashville in June 2012.
Hellberg is a big, lanky netminder that plays the butterfly style but stays deeper in the net with his hands in tight to his body and allows the puck to hit him. He is a smart goaltender who reads the plays well and reacts quickly to position his big body, square to the shooter. The young goalie can over play the angles, needs to stay more upright and improve his timing when going down to cover the lower part of his net. He will get exploited high as the AHL players practice to shoot for the top corners. The Swedish goaltender will take time to adjust his positioning on the smaller ice surface and to the fast style of the North American game.
After signing a NHL entry level contract, Hellberg decide to play in the AHL for the Milwaukee Admirals. He should be the back-up to starter Jeremy Smith but could be assign to the ECHL if he struggles with his game and needs more playing time as a starter.