Inside the NBA's Barkley will host SNL for the third time on January 7 alongside musical guest Kelly Clarkson, who is also making her third appearance.
Barkley last guest starred on SNL in January 2010, when he spoofed Inside the NBA and appeared with Will Forte's popular character MacGruber in a series of taped sketches.
Radcliffe makes his Saturday Night Live debut one week after Barkley's return on January 14.
The Woman in Black actor will be joined by 'Video Games' singer Lana Del Rey.
Saturday Night Live airs at 11.30/10.30c on NBC.
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Watch Charles Barkley in an SNL sketch below (US only):