Kamron Reid, 20, is one of four men on trial for murdering the 21-year-old following an earlier confrontation involving the victim's friend the same night at Gabba's Bar in Darlaston.
Mr Mayer died after being stabbed in the leg with a sword, allegedly by Ramani Sanderson, 20, as violence erupted on Forge Street in July 2019. His femoral artery was ruptured and he died in hospital three days later.
Reid is also accused of being part of the attack which killed Mr Mayer, along with Lewis Green and Joseph Till, both 21.
But his barrister Mr Paul Lewis QC told Wolverhampton Crown Court Reid only went to the scene to play peacemaker as he did not know Mr Mayer and his friends and had "no beef" with them.
Reid initially told police he did not see Sanderson with a knife but changed his story when giving evidence in the witness box.
Mr Lewis said his client was "frightened" by the prospect of being arrested for murder.
He told the jury during his closing speech: "Anyone would be frightened of being arrested for murder. That's right, isn't it?
"He has seen in the press, on the news, he didn't do anything but it's part of joint enterprise. That's the allegation in this case.
"You heard when he gave evidence, he told us why he went there. Not for violence, not to back up Ramani in the attack of people he had never spoken to and had no beef with.
"He went there to bless it up, in his words. To calm things down."
The prosecution claim Reid was one of the "troops" who were "summoned" by Green for the joint attack following his dispute with Mr Mayer's friend, and that it was not credible the other three did not know Sanderson had a weapon.
Reid, of Herberts Park Road, Bloxwich; Green, of Heathfield Lane West, Darlaston; Till, of Summer Street, Willenhall; and Sanderson, of Walsham Road, near Peckham, London, all deny murder. Sanderson also denies possessing a bladed article in a public place. The trial continues.
The trial continues.