I am talking about a tennis player.

The highest he's ranked in the world is 5th.

The highest he's been ranked in the world is 5th.

The verb "rank" can be either transitive or intransitive, so "he has (= he's) ranked" [intransitive] and "he has (= he's) been ranked" [transitive] are both correct.
AnonymousThe highest he's ranked in the world is 5th.
"he's ranked" can be interpreted in two ways: either as "he is ranked" or "he has ranked". Although the latter actually makes more sense in the context of this sentence, the former is generally speaking more usual, so I tend to read it as the former and then the sentence looks wrong.
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Anonymous The highest he's [ ever ]been ranked in the world is 5th.

If you are asking whether the verb "rank" was used passively correctly, the answer is "yes". Between the two sentences, the present perfect version is more correct relative to the phrase " the highest ... is 5th".
 GPY's reply was promoted to an answer.
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