 Lehtonen ranked Juha Leimu of Pelicans in the second round of the SM Liiga defender's goal.In the 2016–17 season he was KooKoo's second best point-keeper and the most powerful defender until the threshold of the Liiga move.In February 2017, Lehtonen spent the rest of the season for the Swedish SHL League in HV71 and he won the Swedish Championship at the end of the season.