What does the cryptic crossword clue "Just for finishers time is up by clock (4)" mean?

The definition is "clock". The wordplay uses acrostic. last letters of "time is up by" = ESPY; definition: "clock" The answer is ESPY.

Just for finishers time is up by clock (4)

Independent Cryptic #11715 | 25 Down | 2024-04-27 flower