On 28 February 2009, Maanoja became seriously injured in a pre-season game against Assyriska Föreningen. He broke his leg in two places, rushing out to stop an Assyriska attack. The injury made him miss the 2009 UEFA European Under-21 Football Championship, hosted in Sweden, in the summer. He also missed the whole 2009 Allsvenskan season, when AIK won the double. He moved back to Honka in 2011, and on 21 February 2012 he signed a contract with the Norwegian First Division club Sandefjord Fotball as a free agent. Sandefjord's head coach Arne Sandstø let Maanoja play the match against Alta in May 2012 instead of Iven Austbø, but Maanoja spent the rest of the season as the reserve goalkeeper. After one season in Norway, he moved back to Finland and signed for RoPS.