Learn Spanish (Latin America): No debemos interferir el uno con el otro durante el saque. - We should not interfere with each other during the serve.

When a reciprocal action uses a preposition like con, de, or a, Spanish places that preposition immediately before el otro. Therefore, "with each other" becomes el uno con el otro.

Why is there no reciprocal pronoun like nos here, such as no nos debemos interferir?

You usually need nos when an action is done directly to each other. Here, interferir connects to the other person using the preposition con rather than a direct object. Because of this structure, the nos is dropped, and we rely entirely on el uno con el otro to express "each other".

If two female players are speaking, does the phrase change?

Yes! The phrase must agree in gender and number with the people involved. Two women would say la una con la otra. If it were a group of three or more people, they would use the plural, like los unos con los otros.

How does el saque mean "the serve"?

It is the noun form of the verb sacar. While sacar usually means "to take out," it is the standard verb for serving the ball in sports like tennis and volleyball.