The most common and most likely answer to this crossword clue is the 9 letter word INTERPOSE
I've seen this crossword clue in The Times
I
N
T
E
R
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E
More clues leading to the result INTERPOSE
- Barge in open site travelling round river
- Barge in season, heading off south east, beyond river
- Put in for rerun, sore and inept
- 4 admitted to post office, in short
- Put in chasing group following Italian giants after small loss
- Muscle in sport I need, cut off!
- Put in for one stripe during manoeuvres
- Come between Italian footballers and model?
- Come between breaks — no respite...
Buddy explains!

The straight part
We know that "Barge in/open site" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case barge in/open site = interpose.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 INTERPOSE mean?
INTERPOSE verb- To insert something (or oneself) between other things.
- To interrupt a conversation by introducing a different subject or making a comment.
- To offer (one's help or services).
- To be inserted between parts or things; to come between.
- To intervene in a dispute, or in a conversation.