Learn Turkish: Kavga eden oyuncuların yüzünden zaman kaybettik. - Because of the players who argued, we lost time.

The word yüzünden literally means from its face. Because it acts like a noun possessed by another noun, it requires the preceding noun or pronoun to take the genitive (possessive) case. So, oyuncuların yüzünden structurally translates to from the face of the players, giving us the meaning due to the players or because of the players.

Could we use sayesinde instead of yüzünden in this sentence?

No, that would sound very strange! Yüzünden is specifically used for negative or undesirable causes, like losing time. Sayesinde is used for positive outcomes, meaning thanks to. Using sayesinde here would sarcastically imply you are grateful to the fighting players for making you lose time.

How does kavga eden translate to who argued? I thought the -en suffix meant the action is happening right now.

The suffix -(y)en (as in eden) creates a subject participle, meaning who/which/that does the action. While it often translates to the present tense, it doesn't have a strict tense of its own. It takes its time frame from the main verb of the sentence. Since the main verb kaybettik (we lost) is in the past tense, kavga eden naturally translates to the past tense who argued or who were arguing.

Why is kaybettik written as one word with a b, instead of kayıp ettik?