CAS said in an emailed statement he was banned for the use or attempted use of a banned substance or method, without giving any further details. Shustov won the gold medal at the European championships in 2010.
The Russian Athletics Federation said on Monday that Shustov's ban was dated from June 5, and his results were disqualified for a period from 2013 to 2017. That means he keeps his European title but is retroactively disqualified from seventh place at the 2013 world championships in Moscow.
The 35-year-old Shustov has not competed since 2016, according to World Athletics records. Shustov told Russian state news agency RIA Novosti he planned to file an appeal. According to the Russian federation's records, he was trained by Evgeny Zagorulko, who is facing charges related to the alleged filing of forged medical documents in relation to another of his athletes, Danil Lysenko.
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