Szabo first competed with the senior national team at the 2012 European Fencing Championships in Legnano. Germany was defeated by Romania in the semi-final, then prevailed over Italy to take the bronze medal. Szabo climbed his first World Cup podium in the 2012–13 season with a victory in the Challenge Chicago after overcoming in the final Olympic champion Áron Szilágyi. At the 2013 European Championships, he was beaten in the second round by France's Vincent Anstett. In the team event, Germany lost against Hungary in the first round and was ranked 5th. For his first participation in World Championships, Szabo was defeated in the second round by Italy's Luigi Samele. In the team event, Germany was edged out by Russia in the quarter-finals and ended up 5th. Szabo finished the season 17th in world rankings.