Section 320AS Row 9SR at Yankee Stadium means that the ticket is good for standing room only on the Terrace Level. This means that you will not have a designated seat, but instead you will stand while watching the game. There are a few places where you can find bar stools or counter tops on this level for people with standing room only tickets, but it is important to get to the stadium early if you want to sit in one of these spots because they tend to fill up quickly.