NBC had serious concerns about Jimmy Fallon’s alleged drinking problems nearly seven years before “Tonight Show” staffers publicly accused the host of getting drunk at work.

Page Six exclusively reported in October 2016 that top-ranking network execs had even warned the comedian to cut back on the booze.

“There were fears that Fallon was out of control and something could happen while he’s out drinking,” an insider told us at the time.

“Things got so serious at one stage that execs feared that Jimmy was splitting up with his wife [Nancy Juvonen] over his drinking, but they patched things up.”

Another source claimed that Fallon, now 48, was a “heavy drinker.”

“He sees himself as somebody who needs image rehabilitation,” the insider told us in 2016, while another pal previously claimed the funnyman had reduced his alcohol intake because he knew he had to “be responsible.”

Months prior to that report, NBC publicly denied that Fallon had any substance abuse issues.

NBC Entertainment Chairman Bob Greenblatt said in a statement in January 2016 that the “Saturday Night Live” alum “doesn’t have a drinking problem that any of us know about.”

“He goes out and has fun, and he’s had some accidents,” the exec added. “There’s been conversations about that, [but] the stories are exaggerated about all of it.”

[Fallon had to have surgery in June 2015 after his wedding ring got caught on a table and “almost ripped [his] finger off. A few months later, he injured his other hand when he fell on a bottle of Jägermeister.]

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However, two current and 14 former “Tonight Show” employees came forward to tell Rolling Stone in a bombshell report published Thursday that Fallon appeared to struggle on set over the years.

One person claimed the “Fever Pitch” star appeared intoxicated while at work in 2017.

Two others alleged his breath wreaked of alcohol on two separate elevator rides in 2019 and 2020.

Fallon’s behavior was also criticized, with one source claiming he acted in an “erratic” manner toward members of his leadership teams.

Some former staffers also claimed the comedian — along with other “Tonight Show” bosses — belittled and bullied their colleagues.

“It was like, if Jimmy is in a bad mood, everyone’s day is f–ked,” an employee told the publication.

“People wouldn’t joke around in the office, and they wouldn’t stand around and talk to each other. It was very much like, focus on whatever it is that you have to do because Jimmy’s in a bad mood, and if he sees that, he might fly off.”

Employees reportedly became so affected by the “toxic” work environment that some were overheard joking about “wanting to kill themselves” and used guest dressing rooms as “crying rooms.”

At least four people sought professional help in therapy for their suicidal ideations, per Rolling Stone.

Fallon has not yet addressed the allegations, but NBC released a statement to the outlet saying they are “incredibly proud” of the late-night talk show and that “providing a respectful working environment is a top priority.”

“As in any workplace, we have had employees raise issues; those have been investigated and action has been taken where appropriate,” the network spokesperson added.

“As is always the case, we encourage employees who feel they have experienced or observed behavior inconsistent with our policies to report their concerns so that we may address them accordingly.”

A show source also told Page Six Thursday that the work environment has changed significantly since showrunner Chris Miller took over in May, as he brought a “renewed enthusiasm and positive energy.”

“He’s exactly what the show needed,” the insider said, while a producer added to us that Fallon is now extremely “engaged” with the staff and “the atmosphere is very different.”