 Complete the following phrase:  The stadium underwent major renovations twice, in 1974 and from 2000 to 2004. In both cases, the renovations were for the upcoming FIFA World Cup. In the 1974 upgrades, the stadium received a partial roof. It underwent a thorough modernization for the 2006 World Cup. In addition, the colour of the track was changed to blue to match Herthas club colours. In addition to Herthas home games, Olympiastadion serves as one of the home grounds for the Germany national football team, and it hosts concerts, track and field competitions, and the annual DFB-Pokal final. It was also the site for six matches of the 2006 World Cup, including the 