Walker grabbed eight rebounds and distributed five assists for the Bobcats, who weathered an 18-4 Memphis surge down the stretch. They hung on for the win when Mike Conley missed a pair of potentially game-tying 3-point attempts in the final 10.7 seconds.
Josh McRoberts netted 12 points for Charlotte.
Conley had 16 points, five assists and five rebounds for the Grizzlies, whose four-game winning streak was snapped. Zach Randolph had 12 points and 11 rebounds.