The most common and most likely answer to this crossword clue is the 6 letter word LOBBED
I've seen this crossword clue in The Guardian
L
O
B
B
E
D
Buddy explains!

The straight part
We know that "cast" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cast = lobbed.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.
What does LOBBED mean?
LOBBED verb- To throw or hit a ball into the air in a high arch.
- To throw.
- To put, place
- To hit, kick, or throw a ball over another player in a game.
- To let fall heavily or lazily.
- To cob (chip off unwanted pieces of stone).