Crossword Genius

Put down as unprofessional (3)

Ross

I believe the answer is:

lay

Here is my best explanation:

I believe this clue is a double definition.

'put down' is the first definition.
(laying is a kind of putting down)

'unprofessional' is the second definition.
(I've seen this before)

'as' acts as a link.

This clue was last seen in Evening Standard