A stocky midfielder, Mählich started his professional career at Wiener Sport-Club before moving to FC Tirol Innsbruck in 1994.

After eight seasons in Graz, he played for some lower league sides as well as for the Austria Wien reserves.

He made his debut for Austria in a September 1992 friendly match against Portugal and was a participant at the 1998 FIFA World Cup.

[5] The following week, they were knocked out by Rapid Wien in extra time in the first round of the Austrian Cup.

After four years without a club - a period during which he worked as a TV pundit - it was confirmed in July 2024 that Mählich had been hired as sporting director of SK Korneuburg.