The most common and most likely answer to this crossword clue is the 8 letter word SPEEDWAY
I've seen this crossword clue in Financial Times
S
P
E
E
D
W
A
Y
More clues leading to the result SPEEDWAY
- Sport that’s fast acquiring drug habit
- Went into power for sport
- Swerve to maintain intense turning – in this sport?
- Fast track that’s obscure making comeback in rock
- Serious upset in power sport
- Process to pursue drug in sport
- Sport in gym with man in swerve
- Wade off into Scottish river for sport
- Serious turns in power sport
- Wade about in a Scottish river for sport
Buddy explains!

The straight part
We know that "sport" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sport = speedway.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 SPEEDWAY mean?
SPEEDWAY noun- A form of motorcycle racing on flat (without camber) oval dirt tracks using motorcycles with neither brakes nor gears.
- A form of bicycle racing on flat (non-banked) oval dirt tracks.
- A racetrack venue designated especially for the sport of auto racing.
- A road for high speed traffic; an expressway.