Luiz Gustavo has stressed Wolfsburg must keep spending if they want to challenge for top honours again.
Wolfsburg enjoyed a successful 2014-15 campaign in which they finished runners-up to Bayern Munich in the Bundesliga and won the DFB-Pokal.
Dieter Hecking's men also made it to the quarter-finals of the Champions League this season, where Real Madrid eventually proved to be too strong.
"When I joined Wolfsburg, they told me they wanted to build a great team," the Brazil international told SportBild.
"But if we really want to become a big team, the people in charge will have to do something again.
"There have always been investments in the team. I can see myself stay here if that continues.
"I want to play against the best and be able to beat them. You need great players for that and a great team."
