Iran's indefinite suspension by the International Judo Federation - for ordering defending champion Saeid Mollaei to pull out of the 2019 World Championships - has been lifted.
Mollaei ignored calls to withdraw from a match to avoid the prospect of facing Israel's Sagi Muki later in the event.
Iranian athletes have been banned from competing in any sport against Israel.
The IJF suspended Iran in 2019 but the Court of Arbitration for Sport (Cas) said the ruling had "no legal basis".
Cas said it found the Islamic Republic of Iran Judo Federation (IRIJF) to have "committed severe violations" of IJF rules, but that a sanction of an unlimited suspension was unlawful.
"Accordingly, the panel partially upheld the appeal and annulled the decision taken by the IJF disciplinary commission on 22 October 2019," said Cas, which announced its decision on Monday.
"The matter has been referred back to the IJF disciplinary commission for its eventual further decisions."
After refusing to withdraw, the 29-year-old beat Russia's Olympic champion Khasan Khalmurzaev in the third round of the men's 81kg event and eventually reached the semi-finals.
He lost to Belgium's Matthias Casse in the last four, with Israel's Muki beating Mollaei's conqueror in the final to win gold.
Mollaei has not returned to Iran since those World Championships in Japan, saying he feared for the safety of himself and his family if he did so.
After spending time in Germany, he now represents Mongolia. In February, he competed in an event in Israel.
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