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ABC was all in on "Roseanne."

That much was clear on May 15, when the network made the show — and its controversial star Roseanne Barr — the centerpiece of its upfront presentation, where it outlined its programming plans for the upcoming fall TV season.

Network execs proudly proclaimed "Roseanne" was the No. 1 show on TV — marking the first time ABC has had such a program in over two decades. Barr appeared in a skit with the "American Idol" judges and sang the Frank Sinatra song "My Way," sending a clear message that she can't be restrained.

They even joked about her propensity to post divisive tweets. Barr quipped onstage that Ben Sherwood, the president of the Disney-ABC Television Group, actually writes the bulk of her tweets, which he later lightheartedly denied.

"If anyone came to play a drinking game based on how many times we mention 'Roseanne,' you're welcome," Sherwood told the crowd after Barr introduced him, endearingly calling her "a woman who has always done it her way."

The network embraced Barr, baggage and all. And now it's paying the price.

ABC is left in a precarious position after it canceled Barr's recently rebooted sitcomTuesday following a string of offensive tweets by the actress. She referred to former Barack Obama adviser Valerie Jarrett as the baby of"muslim brotherhood & planet of the apes," in addition to touting a conspiracy theory about investor George Soros where she called him "a nazi." The social media spiral was met with widespread backlash, and the show was canceled hours later.

Barr, who has repeatedly apologized to Jarrett, returned to Twitter on Tuesday night after "leaving" the site earlier in the day and described her late-night posts as "ambien tweeting."

The swift cancellation, which was widely praised, presents tremendous uncertainty for the network moving forward, as it has a gaping hole to fill in its primetime schedule. There's no obvious replacement for "Roseanne," which aired Tuesdays at 8 p.m. and garnered impressive ratings that many prognosticators didn't foresee.

"This wasn't a choice for ABC," Robert Thompson, a Syracuse University professor whose area of expertise includes TV, told the Daily News. "They knew exactly how this story had to end, and they did it quickly as opposed to sending out a bunch of different press releases and then finally doing it. They took one look at that tweet yesterday and they knew the trajectory. They knew it only ended one way."

Bob Iger, the CEO of Disney, tweeted Tuesday that canceling Barr's show was "the right thing to do."

The timing of the move presents a big challenge for ABC. The bulk of TV advertising deals covering this September to August 2019 will be reached in the next week or two following the networks' upfront presentations earlier this month — a period known as the "upfront marketplace."

"I don't think — given that the upfront market is transpiring now — that any advertiser would feel comfortable today, tomorrow or in the next week or two putting money against that show," says Carrie Drinkwater, the executive director of investments for Media Hub, a division of the Mullen Lowe advertising agency. She noted that 85% of deals will be reached in the coming weeks.

The latest season of "Roseanne" earned an estimated $45 million in ad revenue through its nine episodes this spring, and was poised to earn up to $60 million next season before the cancellation,The Wrapreported. The show had already locked in $22.7 million in advertising for the upcoming season, according to NBC News.

It'll now be up to ABC to figure out how to cover that potential loss. Drinkwater says the network's portfolio remains impressive without "Roseanne" due to other programs such as "Jimmy Kimmel Live!" and "Good Morning America," but ABC is now tasked with finding additional programming that advertisers will find desirable to help fill the void.

"I think they needed to make that decision in order to properly demonstrate where advertising dollars would be, and also to properly demonstrate how they feel about comments and the times that we live in and how they will stand up to that," Drinkwater said.