TAMPA (FOX 13) - One evening last September, Susan Downey remembers her neighbor, Brian Baker calling for her husband, Matt.
"The word we heard the loudest was 'Matt, Matt,'" Susan described in court Tuesday.
Brian Baker was parked in an alley near their home at Westshore Yacht Club in Tampa.
Never suspecting any trouble, Susan told her husband that Baker probably needed help parking his car.
"He had his arms wide out and said 'Brian, what's up? What do you need?'" Susan recalled.
Within seconds, things turned violent.
"Matt screamed 'What are you doing?' The shots just came out. It happened so fast," said Susan.
Prosecutors say Matt was shot nine times by Baker.
"Just like a robot just turned and continued to fire right into to Matt," said Susan.
Susan said she tried her best to stop the bleeding but her husband did not make it. In shock, she asked Baker why he did it but never got an answer - until Tuesday.
During opening statements, Baker's attorney, Dalton McKeever says it was self-defense.
"Both Mr. Downey and Mr. Baker were intoxicated. Both had been drinking all day," said McKeever.
They say earlier in the day Brian Baker and Matt Downey had a physical altercation at a tiki bar near the neighborhood marina.
"Mr. Downey turns to Mr. Baker and shoves him. That's what the evidence, in this case, will show that caused Mr. Baker to fall to the ground," said McKeever.
Hours later, they say Baker was in his car when Downey came at him in a threatening manner.
"Matt Downey comes out with an anger on his face and says, 'What the [expletive] do you want?' in a loud rage," explained McKeever.
Susan Downey, who says she witnessed the shooting, said she never heard any of that.
But later the defense got Susan to admit she was in shock and her memory was likely a bit foggy on certain details.
The trial is expected to last until the end of the week.