The most common and most likely answer to this crossword clue is the 3 plus 6 letter word SET PIECES
I've seen this crossword clue in The Daily Telegraph
S
E
T
P
I
E
C
E
S
More clues leading to the result SET PIECES
- Men on TV co-ordinated manoeuvres
- Synchronise men’s rehearsed moves
- Pawns or knights for corners?
- Prepares to capture rook, say, in carefully planned moves
- Put rooks for e.g. at corners
- Eg king and queen making formal speeches
- Organised plays, having parts on television
- Corners knights?
- Bishops and knights, say, in carefully planned moves
- Regulate misuse of pesticide — it’d cut corners etc
Buddy explains!

The straight part
We know that "corners?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case corners? = set pieces.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.