Leppälahti played in the youth sectors of Espoon Palloseura (EPS) and FC Honka.
[4] On 23 August 2023, Leppälahti was unexpectedly dismissed by KTP,[5] after the club had first exercised their option and extended his contract earlier in the summer.
[6] Prior to his departure, KTP were 10th in the league standings and had gained 20 points in 20 matches, with five wins and five draws.
[7] Later it was announced that Gnistan were granted the league license for 2024 Veikkausliiga season via supplemental process.
[1] Leppälahti has also worked as a sports journalist in 2010s for Jalkapallolehti, Urheilulehti and Elmo, gaining popularity as a critical writer with controversial and provocative style.