The most common and most likely answer to this crossword clue is the 5 letter word SCORE
I've seen this crossword clue in The Sunday Telegraph
S
C
O
R
E
More clues leading to the result SCORE
- Find the net? One can be composed!
- Batsman’s total; made with five boundaries?
- Small company about to be successful
- Nick a result?
- Resentful about conductor's original musical arrangement
- Mark twenty
- Upset about clubs making purchase of illegal drugs
- Distressed about clubs making a number of goals
- Medic at last probes painful scratch
- Music centre: last of records on it
Buddy explains!

The straight part
We know that "mark" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mark = score.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.
What does SCORE mean?
SCORE noun- The total number of goals, points, runs, etc. earned by a participant in a game.
- The number of points accrued by each of the participants in a game, expressed as a ratio or a series of numbers.
- The performance of an individual or group on an examination or test, expressed by a number, letter, or other symbol; a grade.
- Twenty, 20 (number).
- A distance of twenty yards, in ancient archery and gunnery.
- A weight of twenty pounds.
- The written form of a musical composition showing all instrumental and vocal parts below each other.
- The music of a movie or play.
- Subject.
- Account; reason; motive; sake; behalf.
- A notch or incision; especially, one that is made as a tally mark; hence, a mark, or line, made for the purpose of account.
- An account or reckoning; account of dues; bill; debt.
- A criminal act, especially:
- A sexual conquest.
- To cut a notch or a groove in a surface.
- To record the tally of points for a game, a match, or an examination.
- To obtain something desired.
- To provide (a film, etc.) with a musical score.
- Acknowledgement of success