What does the cryptic crossword clue "One’s counterparts work to withdraw concession (5)" mean?

The definition is "concession". The wordplay uses a reversal. OP (synonym="work") + SOP (reversal="a concession") = OPPOS The answer is OPPOS.

One’s counterparts work to withdraw concession (5)

Guardian Cryptic #29569 | 25 Across | 2024-12-18 flower