HAYWARD -- Cort Holbrook, a Livermore software engineer on trial for fatally stabbing a Fremont man during a 2011 road rage incident, took the stand in his own defense Monday in the last day of testimony.

Holbrook steadfastly denied prosecutor allegations that he had changed his story from his initial statements to police.

Holbrook. 43. is charged with murdering Ricky Ziesmer, 48, of Fremont, after an altercation in which Holbrook claims he stabbed Ziesmer in self-defense. Prosecutors allege the killing was an act of revenge.

During testimony Monday, Alameda County deputy district attorney Brian Owens showed jurors a video of Holbrook's initial statement to detectives hours after the March 9, 2011, incident. He grilled Holbrook on inconsistencies between the video and his previous court testimony.

"Isn't the reason you didn't tell (the detective) you stabbed (Ziesmer) more than once is because you knew that if you stabbed him more than once it wouldn't look like self defense?" he asked.

"No," Holbrook responded.

Holbrook has testified that he and Ziesmer exchanged words after Ziesmer cut him off in traffic several times. Holbrook admits making an obscene gesture at Ziesmer and said Ziesmer then threatened to beat him. Holbrook claims he feared for his safety and pulled his truck into a parking lot. Holbrook claims Ziesmer got out of his car and hit him, knocking him to the ground and causing his glasses to fall off.

When Holbrook tried taking a picture of Ziesmer's license plate with his cellphone, he testified, Ziesmer charged. With a small "boot" dagger and cellphone in his left hand, Holbrook has testified that he took a defensive posture and made a motion with the knife, not intending the wound to be fatal.

During the proceedings, Owens questioned Holbrook about conflicting statements he'd made to detectives about when he had tried to call 911, how he had been hit by Ziesmer and where he had aimed the knife. Holbrook repeatedly attributed inconsistencies to being in pain and dazed after the altercation.

"This was a fluid situation," Holbrook told the jury. "I'm not changing my story ... I was defending myself."

On cross-examination, Owens repeatedly asked Holbrook to clarify where he had aimed the knife, referring to his initial statement to the detective.

"There, you point to your left breast," Owens said, referring to the video.

"I was trying for his arm and missed," Holbrook said.

Closing arguments in the trial are expected to start Tuesday.