Translation of Soccer term: disarm

Solution 1:

The action of attempting to take the ball from the opponent player is called "tackling". However, I do not know of any single word describing losing the ball, except for "losing the ball".

Solution 2:

"Steal" would be the most appropriate word based on the context you are using it in.

Merriam-Webster's Dictionary lists the following definition when using "steal" as a transitive verb:

a : to seize, gain, or win by trickery, skill, or daring b of a base runner : to reach (a base) safely solely by running and usually catching the opposing team off guard

For soccer purposes: "Kaka stole the ball from Beckham and is streaking up field!"

How Kaka came to gain possession of the ball - whether Beckham had lost it while attempting to make a fancy play or if Kaka had simply run up to Beckham and kicked the ball out from under his feet - the result is the same. Beckham had the ball until Kaka took it from him.

Solution 3:

"Steal" is used in American English (which might be what you're after as you asked about "soccer"). In British English, dispossess would be more common.

deprive (a player) of the ball

There is also the phrase "caught in possession", but that describes a player with the ball that didn't notice an approaching opponent who then dispossessed him.