I’m unsure about using “according” with a comma.

I know that if it comes at the beginning of a sentence, there will be a pause and a comma needed. For example, “According to the reports, the company has problems”; however, what if we reverse them?

Should it be: “The company has problems, according to reports” or “The company has problems according to reports”

And what about…”Andy Murray is the fittest he has been, according to his trainer”

I would put the comma before "according."