2010-11: Cal Petersen skated for the Chicago Young Americans U18 team in the Midwest Elite Hockey League. In 24 games he had a 2.30 goals against and .923 save percentage. A native of Waterloo, IA, he was drafted by the hometown Black Hawks in the 13th round (185th overall) of the 2011 USHL Entry Draft.
2011-12: Petersen made his USHL debut, appearing in five games for Waterloo, while also playing in the NAHL with the Topeka Roadrunners and skating for the Young Americans U18 team. Petersen was 3-1 with a 2.94 goals against and .902 save percentage in his stint with Waterloo. In two March games with Topeka, both of which went into overtime, he was 1-1 with a 1.86 goals against and .925 save percentage. He played 12 U18 games for Chicago and had a 3.09 goals against an .895 save percentage. Petersen appeared in one game for the USA at the Ivan Hlinka Tournament in August, stopping 8 of 11 shots in 20 minutes of action in the USA's 6-5 shootout win over Slovakia, as Jon Gillies handled the bulk of the goaltending. The USA was 3-1 in the tournament but finished fifth due to a pair of overtime games.
2012-13: Petersen split the goaltending for Waterloo with fellow 2013 NHL Draft hopeful Eamon McAdam, giving the Black Hawks one of the USHL's top goaltending tandems. In 35 games he was 21-11-1 with 3 shutouts and had a 2.97 goals against and .906 save percentage. Petersen played in four of five playoff games and was 2-2 with a 4.26 goals against and .881 save percentage. In October 2012 he committed to playing college hockey at Notre Dame in 2014-15. Petersen was ranked fourth amongst North American goaltenders in Central Scouting's final rankings prior to the 2013 NHL Draft.
Petersen is a quick, athletic goalie who models his game after Tuukka Rask. He does not get scored on often down low because of his quick feet. He has good control of rebounds and catches with his right hand, which poses a challenge to shooters. He is raw and needs much more experience. He is not considered to be a future NHL starter.
Petersen has committed to Notre Dame but will return to his hometown Waterloo Blackhawks for the 2013-14 season. Petersen will wait until senior Steven Summerhays, Notre Dame’s incumbent starter, graduates before moving to South Bend.