Middlesbrough defender Abel Xavier has again tested positive for a banned substance in the B sample following his original test on 29 September.
The 32-year-old Portuguese defender failed the test after Middlesbrough’s Uefa Cup game at Xanthi. He now faces a Uefa hearing and could be banned for a year.
A Uefa spokesman said: “The B sample has confirmed the original findings.”
Xavier said last month: “I am convinced there is a harmless explanation.”
The Portuguese star has been suspended from all competitions while the investigation is underway.
If Xavier is found guilty of taking a performance-enhancing drug he would be the first Premiership player to do so – although several players have tested positive for recreational drugs.
Middlesbrough manager Steve McClaren is backing the player.
“He is protesting his innocence vehemently at the moment,” said McClaren, who has said Xavier is elsewhere in Europe preparing for his Uefa hearing.
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