The most common and most likely answer to this crossword clue is the 6 letter word WINGER
I've seen this crossword clue in The Guardian
W
I
N
G
E
R
More clues leading to the result WINGER
Buddy explains!
The straight part
We know that "Quick footballer/swift perhaps" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case quick footballer/swift perhaps = winger.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 WINGER mean?
WINGER noun- One of the casks stowed in the wings of a vessel's hold, being smaller than such as are stowed more amidships.
- An offensive player who plays on either side of the center.