The most common and most likely answer to this crossword clue is the 9 letter word MYSTIFIED
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Buddy explains!

The straight part
We know that "thrown" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case thrown = mystified.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 MYSTIFIED mean?
MYSTIFIED adjective- Puzzled or confused
- State of enchantment as concerns person or event
- To thoroughly confuse, befuddle, or bewilder.