What does the cryptic crossword clue "Bread and butter opening for tennis player (3,4)" mean?

The wordplay uses a charade (building blocks). PAT (synonym="butter") + CASH (synonym="bread – slang for money") = PATCASH The answer is PATCASH.

Bread and butter opening for tennis player (3,4)

Guardian Cryptic #29630 | 14 Across | 2025-02-28 flower