With less than three months left before the first vote is cast in the Democratic presidential primaries, the party’s presidential hopefuls arrived onstage in Atlanta on Wednesday night knowing that elbows were going to be sharper than ever before. But the first, most aggressive salvo of the night was launched not by one of the party’s frontrunners against another frontrunner, but between two candidates who each desperately needed a breakout moment going into the final pre-primary stretch.

In a withering response to Rep. Tulsi Gabbard’s defense of characterizing former presidential nominee Hillary Clinton’s leadership as the “personification of the rot that has sickened the Democratic Party,” Sen. Kamala Harris ran through a laundry list of Gabbard’s perceived offenses against both party and country, characterizing the Hawaii congresswoman as an opportunist who has cozied up to white nationalists, dictators, and perhaps most damningly, President Donald Trump.

“I think that it’s unfortunate that we have someone on this stage that is attempting to be the Democratic nominee for president of the United States, who during the Obama administration spent four years full time on Fox News criticizing President Obama,” Harris said, prompted to respond to Gabbard’s remarks. If anyone on the stage should be condemned as a poor reflection on the party, Harris continued, it should be Gabbard herself.

“When Donald Trump was elected—not even sworn in—buddied up to Steve Bannon to get a meeting with Donald Trump in Trump Tower,” Harris said, before referring to Gabbard’s refusal to disavow her 2017 meeting with Syrian dictator Bashar al-Assad.

“What we need on the stage in November is someone who has the ability to win, and by that, we need someone on that stage who has the ability to go toe-to-toe with Donald Trump, and someone who has the ability to rebuild the Obama coalition and bring the party and the nation together.”

Gabbard, clearly taken aback by Harris’ prosecutorial breakdown of her perceived offenses against the Democratic Party, shot back that it was “unfortunate” that Harris would “traffic in lies and smear and innuendoes because she cannot challenge the substance of the argument that I am making.”

“It only makes me guess that she will as president continue the status quo,” Gabbard continued, “of regime-change wars, which is deeply destructive.”

“I’m not gonna put party interests first—I am gonna put the interests of the American people first,” Gabbard said.

In an apparent confirmation of Harris’ accusation, an official Trump campaign account pushed out a clip of Gabbard’s remarks on Twitter with an emoji denoting that it was “100 percent” accurate.

The surprisingly bitter contretemps between two candidates who have no on-stage history of acrimony was the first—and most aggressive—smackdown in a debate where the four-way top tier is under growing pressure to draw sharper contrasts, and seize a wider lead, from their opponents, and where others on the stage may be facing their final opportunity to break out from the widest field in modern presidential history.

South Bend Mayor Pete Buttigieg has largely escaped the previous six debates unscathed, with most of his Democratic rivals training their fire on putative frontrunner former Vice President Joe Biden or on progressive darlings Sens. Elizabeth Warren and Bernie Sanders. But as the mayor of Indiana’s fourth-largest city tops recent polls in early-voting states and continues to rake in a small fortune in campaign donations, fellow contenders have been increasingly public with their criticism of his tenure as South Bend, Indiana’s chief executive, as well as his anemic support among key Democratic constituencies.

But Buttigieg isn’t the only candidate facing a potential battering on the state in Atlanta. Biden, whose campaign narrative has been largely overshadowed by the impeachment inquiry against President Donald Trump for actions allegedly targeting his own campaign, is in need of a strong defense, and Warren—whose campaign has been hot on Biden’s heels—faces potential criticism both from centrists who view her “Medicare for All” proposal as deadly to her general election changes, and from progressives who say it doesn’t go far enough, fast enough.

But on a ten-person debate stage—comparatively lean, considering that there are still new entrants to the presidential field as of last week—most of the candidates appeared lost in the crowd, focusing on hitting talking points from stump speeches rather than clearing the field.