The most common and most likely answer to this crossword clue is the 6 plus 6 letter word SECOND FIDDLE
I've seen this crossword clue in The Guardian
S
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More clues leading to the result SECOND FIDDLE
- Another bit of cheating for one not quite fit to be a leader
- . Mo Farah: “Initially, I had led off; that’s less important”
- Fraud on back part of orchestra
- What a sidekick plays, using spare racket
- Little Mo’s racket not the main attraction?
- Subordinate role to play in fraud after short time
- Subordinate to support scam
- One playing for the Scottish ceilidh dances — not the leader
- Little time to manipulate subsidiary figure
- Minor role in yet another swindle
Buddy explains!
The straight part
We know that "What a sidekick plays" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case what a sidekick plays = second fiddle.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.