CNN’s Anderson Cooper sparred with Vice President Kamala Harris on Thursday evening, amid reports of growing “panic” in Democratic circles following President Joe Biden’s performance at the debate on Thursday night.

Biden faced off against his predecessor, former President Donald Trump, in Atlanta, but stumbled over some of his answers and failed to chasten the presumptive Republican nominee. Trump, for his part, spewed a near-constant stream of lies and falsehoods on Thursday but largely refrained from the freewheeling style that harmed his campaign in 2020.

“Listen, first of all, what we saw tonight is the president make a very clear contrast with Donald Trump on all the issues that matter to the American people,” Harris said. “Yes, there was a slow start, but it was a strong finish. What came very clear through the course of the night is that Joe Biden is fighting on behalf of the American people. On substance, on policy, on performance — Joe Biden is extraordinarily strong.”

Cooper pushed back on that assessment, repeatedly questioning the president’s performance while noting some Democrats were already calling Biden’s performance a “disaster.”

“I’m sorry, on substance and policy and performance tonight, the president’s performance tonight clearly was disappointing for his supporters,” the host said. Cooper later added that Biden “was a very different person on the stage four years ago when you debated him. That’s certainly true, is it not?”

“I’m not going to spend all night with you talking about the last 90 minutes when I’ve been watching the last three and a half years of performance,” Harris replied. “It was a slow start. That’s obvious to everyone. I’m not going to debate that point.”

“I’m talking about the choice in November, about one of the most important elections in our collective lifetime,” she concluded.