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Former Housing and Urban Development Secretary Julián Castro is facing criticism for going after former Vice President Joe Biden's memory during Thursday's Democratic debate, but not from Sen. Cory Booker (D-N.J.).

Castro during the third debate questioned Biden's recollection of what he previously said about his health care proposal, mockingly asking him if he already forgot "what you said two minutes ago." Some 2020 Democrats have slammed Castro for this, with former Rep. Beto O'Rourke calling this the kind of "personal attack" we don't "need right now."

But in a post-debate CNN interview, Booker came to Castro's defense, saying he has "every right" to raise these "legitimate concerns" about Biden.

"There's a lot of people who are concerned about Joe Biden's ability to carry the ball all the way across the end line without fumbling," Booker said.

Booker certainly seems to think Biden can't do so, saying there were "a lot of moments" during the debate when the candidates looked at each other while Biden spoke, as he "tends to go on sometimes" and make strange comments like his record player reference.

"There are definitely moments when you listen to Joe Biden and you just wonder," Booker said.

Asked if he's suggesting Biden is too old to be president, Booker said he's not, essentially because these concerns aren't new. "I've listened to Joe Biden over the years and often felt like there were times when he is going on or meandering in his speech," Booker said.

Booker further defended this critique Friday, telling CNN it's "very important" to express these concerns about Biden because "we love our country." Brendan Morrow