In 1935 the offensive midfielder moved to MTK Hungaria in Budapest where he won, alongside players like Gusztáv Sebes and Ferenc Sas the Hungarian championships of 1936 and 1937.

In the early 1930's he was called five times to play for the Austria national football team, for which he scored four goals.

This includes two nominations for the famed Wunderteam, where he played under the management team Hugo Meisl and Jimmy Hogan alongside Matthias Sindelar.

There the team around players like Ernst Ocwirk, Ernst Stojaspal and Lukas "Harry" Aurednik defeated in the huge Maracanã Stadium of Rio de Janeiro the Club Nacional from Montevideo, Uruguay, which had six World Cup winners from the tournament in the previous year in their line-up, with 4-0 Beginning with April 1953 Austrian players aged 30 and beyond became exempt from the ban to play abroad.

In the 1971–72 season "Wudi" Müller made another comeback on the coaching bench of Austria, but this remained a venture as hapless as his previous one.