We claim the ornamental design for a tennis ball container overcap, as shown and described.
FIG. 1 is a side perspective view of a tennis ball container over cap, shown in a position of use with exemplary environmental subject matter;
FIG. 2 is a top, side perspective view of the tennis ball container over cap of FIG. 1, shown with the exemplary environmental subject matter removed to show aspects of the design not visible when combined;
FIG. 3 is a bottom, side perspective view thereof;
FIG. 4 is a top view thereof;
FIG. 5 is a bottom view thereof;
FIG. 6 is a first side view thereof; and,
FIG. 7 is a second side view thereof.
The broken lines are shown for the purpose of illustrating both parts of the article as well as exemplary environmental subject matter. The logo shown in broken lines in the drawings, is a registered trademark of Wilson Sporting Goods Co. None of the broken lines form part of the claimed design.