Joe Biden came to Barack Obama's defense Thursday after Democratic presidential candidates' sharp critiques of the popular former president's legacy during the second presidential debate.

"I was a little surprised at how much incoming there was about Barack, about the president," Biden told reporters Thursday in Detroit. "I'm proud of having served with him, I'm proud of the job he did, I don't think there's anything he has to apologize for. And it kind of surprised me, the degree of the criticism."

Biden, who held his ground and fought to solidify his front-runner status in Wednesday's debate, said he hoped the next round would focus on President Donald Trump, whom all the candidates hope to defeat in November 2020.