We're into week four of the Johnny Depp-Amber Heard defamation trial, and as expected, the wild accusations continue to fly at a furious pace.

Yet another witness for Team Depp took the stand on Monday, and once again, Heard was accused of hitting, spitting on, and hurling insults and objects at her ex-husband.

This time, it was Depp's former bodyguard, a man named Travis McGivern, who testified that he witnessed numerous fights between Depp and Heard, some of which became violent.

McGivern said that toward the end of their relationship, the couple fought "pretty regular; every other night, several times a week."

He says that Heard would call Depp a "f--king deadbeat dad, f--king washed up, f--king c--t... you name it - she's spewed it."

The bodyguard detailed one incident, in which he saw Heard throw a can of Red Bull at Depp.

McGivern says that he stepped between the dueling partners, "because I didn't want my client getting hit with anything else". 

"At one point she spit at him," he added, noting that there was "a lot of verbal vitriol," with Depp "giving as good as he got." 

"The F-word is my favorite word, and it was being thrown around to the point where I was uncomfortable," McGivern testified.

"He was mad, he was upset especially after she tried to spit on him."

It was then, the bodyguard recalled, that the argument truly became violent.

"At that point, out of the corner of my eye, I saw a fist and an arm come across my right shoulder, and I heard and saw a closed fist contact Mr. Depp in the left side of his face," he claimed.

"That was Ms. Heard's fist. Amber Heard's fist."

From there, McGivern recalled that he and Depp were both momentarily in shock following the punch.

"The initial look on his face kind of mirrored mine, kind of a look of shock," McGivern recalled.

"What just happened, where did that come from."

At that point, McGivern recalls, he instructed Depp to leave the property.

"I decided I wasn't going to let Mr. Depp get hit any more.I told him we were leaving, it wasn't up to him any more. Just for his safety," he said.

"I'd let him get hit by a Red Bull can, I'd let him get punched... my job is to ensure the safety and well-being of my clients, and I felt like I hadn't done that. So it was my time to do my job and get him out of there."

Depp pointed to the bruise on his own face and said "'that's your fault."

"He had a nice little shiner," McGivern said.

"Definitely swollen and red. It wasn't black and blue yet."

Also taking the stand on Monday was Depp's talent manager Jack Whigham.

Whigham's testimony may not be as tabloid-friendly as the recent tales of blow-out fights, but he's crucial to Depp's claim that he lost out on millions in income as a result of Heard's abuse claims.

According to Whigham, In the nearly four years since Heard published her op-ed in the Washington Post, Depp has received zero offers to star in studio films.

The manager says that even Depp's most recent project -- the low-budget indie film Minamata -- was jeopardized by the article, in which Heard identified herself as a survivor of domestic violence, but did not mention Depp by name.

"It was very very difficult to keep Minamata together, the financing became shaky, the budget came down, Johnny's fee had to come down to save the movie," Whigham testified.

Whigham also confirmed that plans for a sixth Pirates of the Caribbean movie -- for which Depp reportedly would have been paid $22.5 million -- were scrapped in the wake of Heard's allegations.

Obviously, it wasn't a good day for Team Heard, but with three weeks of testimony remaining, this trial is far from over.

Insiders say Heard is still planning to take the stand at some point.

And if her testimony is anywhere near as explosive as Depp's it could easily shift the balance, both in the courtroom and in the court of public opinion.