Mikaelsson, who started for Djurgårdens IF , won his first and only Swedish championship title at the Swedish Championships in 1957. In the same year he was awarded the Sällskapet Gamla Djurgårdare's guldplakett .
In December he started at the Four Hills Tournament 1957/58 . However, he only denied jumping on the Schattenbergschanze in Oberstdorf . Despite a good 10th place, he did not take part in the other competitions of the tour and so only landed 55th place in the overall ranking.