Which sentence uses the correct punctuation?

our football team had two injured players; we lost the game.
our football team had two injured players we lost the game.
our football team had two injured players, we lost the game.
our football team had two injured players; so we lost the game.

Our football team had two injured players; we lost the game.

Explanation:

One of the most common uses of semicolon is to join two independent clauses without having to appeal to a conjunction (such as "and"). In this case, we have "Our football team had two injured players" and "We lost the game". Both of them are independent clauses, therefore the use of semicolon is correct in this sentence.