He made his first appearance on 19 January 2014 in a 2-0 away win against U.S. Sassuolo Calcio and he scored his first goal for the club in a 3-3 away draw against Lazio.
Tachtsidis finally made his Serie A debut for Genoa on 23 August 2015 away to Palermo as a 68th minute replacement for Diego Capel.