NHL star Bobby Ryan -- who's battled substance abuse issues in his career -- was arrested on Monday at an airport after cops say he appeared to be wasted inside a terminal.
According to court documents, obtained by TMZ Sports, the incident happened at the Nashville International Airport in Tennessee ... after Ryan allegedly stole items from a store.
Cops in the documents say Ryan was captured on CCTV taking the goods without paying for them, before he eventually put them on a counter and entered a bar nearby in the concourse.