Metallica are getting really good at performing the national anthem, and that's because of all the practice they're getting. They first performed the song at a 2013 San Francisco Giants game, and it wasn't exactly a home run, if you catch my drift. The following year, they did it again, and it sounded better, but I think they finally nailed it this time. The band performed ahead of Game 5 of the NBA finals between the Cleveland Cavaliers and their hometown Golden State Warriors.
Here's some footage of them from the X Games as well:
[youtube]https://www.youtube.com/watch?v=9P4Ur_lzpdk[/youtube]