FIG. 1 illustrates a top view of the claimed design for a knife guard;
FIG. 2 illustrates a front view thereof;
FIG. 3 illustrates a left-side view thereof;
FIG. 4 illustrates a right-side view thereof;
FIG. 5 illustrates a rear view thereof;
FIG. 6 illustrates a bottom view thereof;
FIG. 7 illustrates an internal cross-sectional view taken through line 7—7 of FIG. 2; and,
FIG. 8 illustrates a perspective view thereof.