 Pääjärvi akaita kutanga kwake kwenyika kuSweden aine makore gumi nemana nechikwata chepasi pegumi nematanhatu mumwaka wa2005-06; mwaka unotevera, akazove mutungamiri wekurova weU16. Munguva ye2008 World Junior Ice Hockey ChampionshipsmuPardubice neLiberec, Czech Republic, pazera remakore gumi nematanhatu nemwedzi misere, akazova mutambi mudiki pane vese akambotambira Sweden panguva yeWorld Junior Hockey Championship. Munguva yemutambo, akarova chibodzwa chimwe, uye akabatsira Sweden kuenda kumagumo paakabatsira Mikael Backlund paSweden yekuwedzera nguva yekukunda mutambo kurwisa Russia mumasemifinal. 