Walker, who broke her nose in the regular season finale against Auburn on Sunday, made seven of 12 from the field, including one of five from behind the arc, and six of six from the line on her way to the 21
points. She added eight rebounds and two assists.
Kentucky (16-11) had four other players in double figures in the game. Dre'una Edwards had a double-double with 18 points and 14 assists, while All-American Rhyne Howard had 14 points, four assists, three rebounds and two steals.
Jazmine Massengill had 12 points, seven assists and six rebounds for the Cats, while Robyn Benton had 12 points, four rebounds, two assists and two blocked shots.
Kentucky held advantages in points off turnovers (21-14), rebounds (47-25), second-chance points (10-2) and points in the paint (52-44).
Kentucky will face second-seeded LSU in Friday's quarterfinals. Tipoff is set for 7 p.m. ET and the game can be seen on the SEC Network.