2007-08: Nathan Lieuwen spent most of the season with the Westside Warriors of the BCHL, but also appeared in three games for the WHL's Kootenay Ice. He registered a 3.27 goals-against average while posting a .910 save percentage.
2008-09: Lieuwen appeared in just 37 games for Kootenay (WHL) due to concussion issues which prevented him from finishing the season or playing in the playoffs. Lieuwen logged a 2.95 GAA and .885 save percentage and was 14-12 with two overtime losses. Lieuwen played in the 2009 CHL Top Prospects Game, but struggled in Team Cherry's 6-1 loss. He was ranked 11th amongst North American goaltenders in Central Scouting's final rankings prior to the 2009 NHL Draft but was not selected.
2009-10: Lieuwen missed much of the season due to post-concussion issues before finally feeling symptom-free towards the end of the season. He appeared in 26 games for Kootenay with Todd Matthews handling the bulk of the goaltending. Lieuwen was 10-10 for the year with a 3.09 GAA and .896 save percentage. He appeared in three playoff games and was 0-1 with a 1.91 GAA while stopping 33 of 37 shots faced. Lieuwen was not among the 30 North American goalies in Central Scouting's final rankings and was not drafted in the 2010 NHL Draft.
2010-11: Lieuwen assumed the starting role for Kootenay in his third WHL season and after a solid regular season was even better in the playoffs during the Ice's run to the Memorial Cup. In 55 games during the season he was 33-16 with four overtime losses and three shutouts and had a 2.79 GAA and .903 save percentage. After losing two of the first three playoff games to Moose Jaw in the first round, Lieuwen and the Ice won 15 of the next 16 games. Lieuwen was named WHL Playoff MVP after finishing with a 2.24 GAA and .923 save percentage. In five Memorial Cup games he was 2-3 with a 3.18 GAA and .890 save percentage. In his third year of eligibility he was selected by Buffalo in the 6th round (167th overall) of the 2011 NHL Draft.
2011-12: Lieuwen was one of the WHL's busier goalies in his final season with the Kootenay Ice — appearing in 57 regular season games and then skating in all four games in the Ice's playoff series with Edmonton. He was 27-28, with eight losses in overtime, and had 3 shutouts with a 2.50 goals against and .914 save percentage during the regular season as Kootenay finished fourth in the Central Division. He was 0-4 in the series with the Oil Kings with a 3.53 goals against and .896 save percentage. Lieuwen signed a three-year entry-level contract with Buffalo in May 2012.
A lanky, 6’5” goaltender, Lieuwen covers a lot of the net with his size and has good technique. The Kootenay Ice alum got better every season and has the potential to become an NHL goalie one day, either as a backup or a journeyman starter.
One of Rochester’s two new goalies, Lieuwen will battle Connor Knapp for playing time behind David Leggio. There is a chance Lieuwen gets sent to the ECHL, but it is not so much a setback as it is a logical move to get Lieuwen more playing time.