Tournament organisers have condemned a spectator who appeared to confront England star Billy Vunipola following Saracens' Heineken Champions Cup semi-final victory over Munster.
Vunipola scored Saracens' second try in an impressive 32-16 semi-final triumph.
A picture of the incident showed Vunipola being approached by a man wearing a Munster shirt, gesturing at him with his fingers as Vunipola joined team-mates on a lap of honour.
EPCR have condemned a spectator who appeared to confront England star Billy Vunipola
The number eight had been booed most times he touched the ball at Coventry's Ricoh Arena, where Munster fans heavily outnumbered Saracens supporters among a 16,000 crowd.
Vunipola received formal warnings from his club and Rugby Football Union in the past week after he posted on social media that 'man was made for woman to procreate that was the goal no?'
He also liked a social media post from controversial Australian star Israel Folau that stated 'hell awaits' for homosexuals.
Vunipola was in form as Saracens pulled off a 32-16 victory in the semi-final clash
A few rainbow flags - symbol of the lesbian, gay, bisexual and transgender movements - were visible among the crowd in Coventry.
In a statement, European Professional Club Rugby said: 'EPCR does not condone the entry of a spectator to the field of play.
'Following the regrettable incident at the Ricoh Arena, the spectator in question is currently being detained by the stadium authorities.'
Vunipola, meanwhile, said there was 'no intention to hurt anyone' following his social media post and support for Folau.
Vunipola said after Saturday’s game: ‘It was probably insensitive, but also something I strongly believe in.
‘I’ll probably not be as honest as I have been about things that probably hurt a lot of people. I know that now.
‘I’m not going to change the happy-go-lucky person I am. My faith