The most common and most likely answer to this crossword clue is the 7 letter word RUBBERS
I've seen this crossword clue in The Guardian
R
U
B
B
E
R
S
Buddy explains!
The straight part
We know that "Protection for an American/series of games" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case protection for an american/series of games = rubbers.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 RUBBERS mean?
RUBBERS noun- Pliable material derived from the sap of the rubber tree; a hydrocarbon polymer of isoprene.
- Synthetic materials with the same properties as natural rubber.
- An eraser.
- A condom.
- Someone or something which rubs.
- The cushion of an electric machine.
- The rectangular pad on the pitcher's mound from which the pitcher must pitch.
- (in the plural) Water-resistant shoe covers, galoshes, overshoes.
- Tires, particularly racing tires.
- A hardship or misfortune.
- In relation to a series of games or matches between two competitors where the overall winner of the series is the competitor which wins a majority of the individual games or matches:
- A rubber match; a game or match played to break a tie.
- The game of rubber bridge.
- Rubber overshoes; galoshes.
- A disease of sheep, with great heat and itchiness.