Roger Stone, a former adviser and longtime friend of President Donald Trump, played a pivotal role in getting former campaign chairman Paul Manafort a job, three former Trump campaign officials told The Daily Beast.

Manafort, now the subject of a FBI investigation pertaining to alleged connections between Russian officials and Trump’s campaign, initially joined the campaign in April 2016. His role began with delegate operations, ensuring that the Republican National Convention went off without a hitch and ended in Trump securing the nomination. By May, Manafort was named the campaign chairman and by June, Trump’s first campaign manager, Corey Lewandowski, was out.

According to the officials familiar with the deliberations, at the outset of Stone’s time with the campaign, he made a strong case to Trump to bring in Manafort. Manafort himself backs that version of events up in an interview for the upcoming Netflix documentary Get Me Roger Stone, which premieres at the Tribeca Film Festival on April 23.

“It was all Stone. Every bit of it was Stone. Right down to suggesting that he go salary-free,” one source familiar with the process told The Daily Beast.

As detailed in a recent New York Times article, Manafort reached out to Trump with memos in February 2016, pitching himself as a professional who could help Trump’s operation. According to the Times report, Thomas J. Barrack Jr., a friend of Trump’s who went on to become the chairman of the Presidential Inaugural Committee, provided Trump with the Manafort memos. Trump subsequently requested a meeting with Manafort, according to the paper.

That’s where Stone came in.

“After Barrack brought Paul to the president, Trump called Stone for a recommendation and they had a long conversation,” one former Trump campaign official told The Daily Beast. “Paul’s offer came soon after.”

Neither Barrack nor Manafort responded to a request for comment from The Daily Beast.

“Roger’s relationship with Trump has been so interconnected that it’s hard to define what’s Roger and what’s Donald,” Manafort says in the documentary. “While it will be clearly a Trump presidency, I think it’s influenced by a Stone philosophy.”

Stone and Manafort worked together in the 1980s for the lobbying firm Black, Manafort, Stone, and Kelly, whose group of clients was referred to as the “torturers’ lobby.” And Stone was further compelled to get his old friend involved in the presidential campaign by his dislike of Lewandowski, later saying after the campaign manager was let go that he was “wisely fired.”

“You know Stone has a hard-on like a dog with a bone,” a person familiar with the deliberations told The Daily Beast. “He just won’t stop doing something. He hates Corey Lewandowski. He was looking for a thousand ways to undo Corey.”

Stone’s call with Trump, which allegedly came after the review of the memos that Manafort sent the candidate, was referred to by one source as “pivotal.”

“All the characterizations I’ve heard—even excluding Roger’s own perspective—made it a closer call,” one source told The Daily Beast. “Informing Trump’s confidence in the decision. Sealing the deal.”

Stone’s alleged behind-the-scenes wrangling was a result of his desire to see Trump succeed, and he purportedly didn’t think Lewandowski was the person who could accomplish that.

“Roger had a lot of ideas, and he was frustrated and he knew how to keep Trump in line, and he wanted him to succeed,” one source familiar with the decision-making told The Daily Beast. “Roger just wanted to get the thing back on track and Manafort was a perfect answer.”

Stone’s official split with the campaign in August 2015 is a tale told very differently by the two sides. Stone says he quit, while the Trump campaign says he was fired. But as he puts it, Stone was—and is—always trying to do things for the ultimate benefit of Trump. He wanted him to run for president as far back as 1988 and advised him once again in 2000, when Trump toyed with running on the Reform Party ticket.

Even now, as Stone spends time on InfoWars suggesting that Trump’s own son-in-law, Jared Kushner, is undermining his administration by providing damaging stories about chief White House strategist Steve Bannon to outlets like MSNBC’s Morning Joe, Stone suggests he’s doing it for the president’s benefit.

“They would like him to be more mainstream, more establishment,” Stone said recently, referring to Kushner, chief of staff Reince Priebus, and deputy national security adviser Dina Powell. “They want him to be popular when he goes to Malibu or the Upper West Side. But I don’t think Donald Trump cares about how he’s perceived in those places. He has no interest in kowtowing or ass-kissing for the establishment. So I think that his advisers are trying to push him in the wrong direction.”

Although he often is quick to take credit for his political maneuvering and influence, Stone was not so quick to indulge The Daily Beast in discussing his role in getting Manafort a job.

“Sorry I only respond to inquiries from legitimate news organizations. Fake News sites like the one you work for don’t qualify,” he wrote in an email to The Daily Beast.