Ghana striker Samuel Tetteh scored on his 23rd birthday on Sunday as LASK Linz beat Altach 2-0 in their Austrian league opener.
Tetteh broke the deadlock with a delightful finish early in the game at the Arena Marchtrenk.
Klauss grabbed the second in the 79th minute to seal the victory.
The former WAFA star is in his third season for LASK Linz on loan from Red Bull Salzburg.
Tetteh scored four goals in 21 league appearances last season.