But it turns out Rosenstein and Sessions never discussed such concerns with one key person: Comey himself.
Specifically, according to sources familiar with the matter, at no point in the weeks and months before Comey's termination did Deputy Attorney General Rosenstein or Attorney General Sessions tell Comey they were uneasy about his leadership or upset over what Rosenstein later called Comey’s "mistaken" decision to announce the results of the FBI investigation into Hillary Clinton's private email server last year.
The failure to flag any such concerns to Comey before terminating him is part of what makes the former FBI director feel so blindsided. It's also part of the story he's planning to tell lawmakers next week when -- barring a last-minute schedule change -- he testifies publicly for the first time about his axing, and about alleged collusion between Trump associates and elements of the Russian government to influence last year's presidential election.
As one source put it: He’s "angry," and he wants the public to understand why.
Some of what he may discuss seems more personal, such as a recounting of how he learned he was fired -- he saw the news on TV while addressing FBI agents in Los Angeles. His wife also found out by watching TV, while her husband was on the other side of the country.
But most of Comey's testimony before the Senate Intelligence Committee on Thursday is expected to touch on grave matters of national security and allegations of espionage and improper influence.
He's expected to echo remarks made last week from former CIA Director John Brennan, who told lawmakers he was "worried" after the U.S. intelligence committee discovered "a number of" contacts between Trump associates and Russian operatives.
Sources familiar with Comey's thinking said he's also ready to discuss whether he felt pressure from Trump or other administration officials to curtail the FBI's probe of alleged ties between the Russian government and members of Trump’s circle.
In particular, Comey is preparing to answer questions over memos he drafted detailing some of his conversations with Trump.
In one memo written after a February get-together, Comey recounted how the president suggested the FBI should drop its investigation of Lt. Gen. Mike Flynn, the national security adviser who was forced to resign for lying to administration officials about his contacts with the Russia's ambassador to the United States.
"I hope you can see your way clear to letting this go, to letting Flynn go," Comey quoted Trump as telling him that day.
After learning of the memos, the top Democrat on the Senate Intelligence Committee, Sen. Mark Warner, D-Virginia, said the president's "concerning" actions were now "beyond troubling ... [by] a factor of 10."
White House press secretary Sean Spicer disputed Comey’s account of the president's remarks, saying it "is not an accurate representation of that meeting." Spicer didn't elaborate.
Unless a last-minute claim of executive privilege from the White House halts Thursday’s hearing, Comey will have an opportunity -- under oath -- to affirm his version of events.
As Warner recently told reporters about Comey: "He deserves to tell his story to the American people."
In his letter to Trump, Rosenstein called Comey "an articulate and persuasive speaker."
However, "I cannot defend the Director's handling of the conclusion of the investigation of Secretary Clinton's emails, and I do not understand his refusal to accept the nearly universal judgment that he was mistaken," Rosenstein said. "The FBI is unlikely to regain public and congressional trust until it has a Director who understands the gravity of the mistakes and pledges never to repeat them."
Asked whether Comey was ever given a chance to make that pledge, or ever told by Rosenstein or Sessions that his actions were wrong, a Justice Department spokeswoman said, "I won’t comment on that."