κλωτσάει is used more often. But in some rural villages κλωτσά is also used, to shorten the word
Was this a listening exercise? There, you have to type what you hear, not something that would be grammatically correct but is not what the voice said.
In the English-to-Greek translation, κλωτσάει should have been accepted for at least six months (the date of the last change to this sentence).
Athletes don't generally kick balls, they run or jump or throw - but sportsman again isn't allowed here.