A man died at a Jessie J gig in April after his throat was slashed in a "one-second" attack by another reveller, a court in England heard on Monday.
Ashley Charles is accused of plunging a broken beer bottle into Philip Sherriff's face and neck at London's Pulse nightclub, shortly after the Price Tag hitmaker had performed.
All I can say is my thoughts, love and respects are with the family and children of the man who attended the Blackberry gig last week who sadly lost his life this morning.
A jury at London's Old Bailey court was told Charles became "annoyed and irritated" after the two men had a tense exchange at the busy bar, before grabbing Sherriff's beer bottle and stabbing him with it.
Prosecutor Duncan Penny said, "Witnesses describe seeing the blow as a swipe or slash. Undoubtedly it all happened very quickly indeed. Perhaps no more than a second. One second to take a life".
Jessie J was left devastated after learning Sherriff died at her show, paying tribute to the dad-of-two after he passed away four days after the attack.
She tweeted, "I am lost for words. All I can say is my thoughts, love and respects are with the family and children of the man who attended the Blackberry gig last week who sadly lost his life this morning. So sad..".
Charles, 26, denies murder. The case continues.