Pedzisa mutsara unotevera: Rantanen akaenderera mberi nekufambira mberi kwake muchikwata chechidiki cheFinland mukuwana kusarudzwa ku
2015 World Junior Championships muToronto. Pasinei nokuva panzvimbo yechinomwe, Rantanen akawana zvibodzwa zvina mumitambo mishanu kuti awane mutambi wepamusoro-vatatu pakusarudzwa kwechikwata.