Question: When was the arena that hosted the 2015 Audi quattro Cup officially opened ?
Sentence (from "2015 Audi quattro Cup"): The 2015 Audi quattro Cup (also known as the Audi quattro Cup presented by SalzburgerLand for sponsorship reasons) was inaugural edition of mini men's football friendly tournament at the Red Bull Arena in Salzburg.
Relevant evidence: Yes