Ex-British and Commonwealth cruiserweight title contender Denzil Brown Senior - who was coaching his boxer son Denzil Browne Junior - is standing trial at Leeds Crown Court over Christopher Lewis's death outside his home on Reginald Street on August 1 last year.
The jury has heard gunman Steven Grey and Jonathan Gledhill - who acted as a "stalker" - were convicted of murdering Mr Lewis following a trial in July because he was a member of a rival drug dealing gang called the Flock.
Three others - Denzil Browne Junior, Owen Clarke and Lewis Pearce - were found guilty of assisting an offender following the July trial.
Pearce 27, of no fixed address, Browne Junior, 23, of Oaklands Crescent, Gipton, and Clarke, 26, of Haw Avenue, Yeadon, helped the killers get away from the Chapeltown area afterwards.
Grey, aged 38, of Town Street, Armley, fired the fatal shot before he and 38-year-old Gledhill, of Dib Lane, Roundhay, ran away for around five minutes.
Denzil Brown Senior, of Parkfield Court, Morley, is standing trail alone. He denies murder.
The prosecution claim Brown Senior, 50, drove Grey and Gledhill away from Chapeltown in his Mercedes 4x4 following the shooting.
It is alleged Brown Senior dropped Grey and Gledhill off at the border of Chapeltown and Chapel Allerton before returning to the area where the killing happened.
The prosecution say Brown Senior then telephoned his son Denzil Browne Junior, who in turn called Owen Clarke who got in his car and went to pick up Grey and Gledhill.
Prosecutors claim Brown Senior was not connected to gang related activities but got involved after his son Denzil Browne Jnr was seriously injured when he was attacked by Flock gang members in a violent clash in Leeds city centre three days before the killing.
Browne Jnr was attacked with an axe and a scythe and suffered injuries including slash wound on his back.
The court heard Browne Jnr sent photos of his injuries via Whats App to his father, who was on holiday in Florida.
Giving evidence at the start of the defence case, Denzil Brown Senior answered questions from his barrister Mark George QC.
Brown Senior told the court he was a professional boxer for 12-years and fought and lost a British cruiserweight title bout against Dennis Andries in 1995.
The jury was shown a poster advertising that boxing match, which was third on a card led by 'Prince' Nassem Hamed v Armando Castro.
Brown Senior also lost against Chris Okoh in a cruiserweight Commonwealth title fight in 1997.
Brown Senior told the court he is a British Telecoms engineer who also trains six professional fighters, including his son.
Brown Senior said his son was in training for a fight in October 2018 when he was attacked.
Mr George asked him: "What was your reaction when you got those messages and saw those pictures?"
Brown Senior: "I just thought 'what's going on here with this boy?' I was a bit disappointed because I did leave him in a training camp."
Mr George asked Brown Senior: "How did you feel as a father seeing photos of this [the stab wound]?"
Brown Senior replied: "It's worrying because anybody would be worried if your son had been stabbed like he had."
Mr George asked: "Did it make you angry?"
Brown Senior replied: "It didn't make me angry - it just made think what is going on here with this boy here? I couldn't be angry because I didn't know what had happened."
"It's said you decided to take some form of revenge?"
"No sir, not at all."
Mr George asked: "Did it make you think any thoughts of violence or vengeance to anyone?"
Brown Senior: "No sir, none whatsoever."
The jury has been told Brown Senior arrived back in Leeds from Florida on the morning of August 1, the day Mr Lewis was shot.