The most common and most likely answer to this crossword clue is the 5 plus 7 letter word MIXED DOUBLES
I've seen this crossword clue in Financial Times
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More clues leading to the result MIXED DOUBLES
- Large cocktails for a tennis foursome?
- Tennis match associated with oversized shorts
- Tennis game, then assorted large drinks
- Use bold arrangement that gender-balanced quartet plays
- Tennis match is repeated on compound
- Tennis shorts?
- Lob's due in a tennis match?
- Pairs game coming as result of unusually bold use?
Buddy explains!
The straight part
We know that "Tennis game" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case tennis game = mixed doubles.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.