[1] He was a key member of the Strasbourg team that finished second in the 1934–35 Championship and reached the final of the cup in 1937.
When Alsace was de facto annexed by the Third Reich, Fritz Keller elected to play for SS side SG SS Straßburg in the Gauliga Elsaß rather than continuing with RC Strasbourg's ersatz, Rasensport Club Straßburg.
[2] According to some of his former teammates at RCS, this was more an opportunistic move than a real ideological gesture as the SS were offering significant rewards to build up the best team in Alsace.
Keller had his first cap for France on 10 May 1934 against the Netherlands and participated in World Cup 1934, playing one game against Austria's Wunderteam.
His younger brother Curt Keller also had one cap with France in 1937 but, at that time, Fritz's career for the national team had ended.