With the help of PowerPoint visuals, West spent hours hammering home his argument.
He broke down Zimmerman's 911 call in which he first reported seeing Martin and told about following him.
"Little did George Zimmerman know at the time in less than 10 minutes from him first seeing Travyon Martin that he, George Zimmerman, would be suckered punched in the face, have his head pounded on concrete and wind up shooting and tragically killing Trayvon Martin," West told jurors.
West also deconstructed a 911 call a neighbor made, in which it is possible to hear screams and a shot in the background that West said was the sound of the fatal bullet.
As the dramatic recording audio filled the courtroom, Zimmerman showed no emotion. Martin's mother left the courtroom.
"At the moment this actually became physical was that Trayvon Martin -- I will use my words -- that Trayvon Martin decided to confront George Zimmerman," West said. "That instead of going home. He had plenty of time. This is, what, 60 or 70 yards. Plenty of time. He could of gone back and forth four or five times."
West quoted a witness named John Good who described the fight. "He called it a 'ground and pound' by Martin, who he said was on top of Zimmerman, beating him."
"He saw enough that this was serious," West said. Zimmerman cried out for help, looked at Good and said, "help me." But the beating continued while Good went inside his home to call 911, West said.
There was a shot. Shortly afterward, according to West, Zimmerman said Martin "was beating me up, and I shot him."
West also disputed the prosecution's claim that Martin was unarmed.
"Travyon Martin armed himself with the concrete sidewalk and used it to smash George Zimmerman's head," said West. "No different than if he picked up a brick or smashed his head against a wall. That is a deadly weapon."
West showed jurors photos taken of Zimmerman after the fight. "What you can really see in these pictures that you will have in evidence are the lumps," West said. "The big knots on each side of his head. Consistent with having his head slammed into concrete."
Among the first prosecution witnessed called was the 911 dispatcher who took Zimmerman's call before the shooting. Seat Noffke testified that he was trained to give general commands instead of direct orders to people.
When Zimmerman said he was following Martin, Noffke told him, "Okay we don't need you to do that." Noffke told the prosecutor he's liable for any direct orders he gives someone.
On cross-examination, defense attorney O'Mara pointed out that Noffke asked Zimmerman, "Which way is he running?"
"If you tell somebody twice to let you know if the person that they're concerned about is doing anything else -- do you think they're going to keep their eye on them?" asked O'Mara.
"I can't answer that," said Noffke.
"You did tell him twice to let you know if that guy did anything else," said O'Mara.
"Yes sir," said Noffke.
Noffke went on to say he only wanted a location of the suspect for officers and that he never told Zimmerman to follow or keep his eye on Martin.