Bid first (4)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
open
'bid first' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for open that I've seen before include "Contest that includes all comers" , "Frank - accessible" , "Not yet decided - to start" , "Frank - ready for business" , "with no clear favourite" .)