London - Troubled Saracens have been hit with a misconduct complaint after being investigated for allegedly using prop Titi Lamositele when he was ineligible in a European Champions Cup win against Racing 92.
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Saracens told European Cup organisers that United States international Lamositele's work permit expired the day before the holders beat Racing 92 in the pool game to reach the quarter-finals.
The 24-year-old is believed to have been eligible when Saracens' matchday squad was announced, but his work permit had expired before the January 19 fixture.
An administrative error by Saracens is said to have led to Lamositele being allowed to play.
A European Professional Club Rugby (EPCR) statement said that Lamositele may have been ineligible when he came on as a replacement in the 60th minute "due to an inadvertent administrative error on behalf of the club".
An independent disciplinary committee will hold a hearing on the issue later on Friday.
A fresh punishment would be another blow in a wretched season for Saracens, who had been relegated from the Premiership the day before the Racing 92 match following persistent salary cap breaches.
Saracens are due to play Leinster in the Champions Cup quarter-finals in April.