diff --git a/src/mame/video/decocass.c b/src/mame/video/decocass.c
index 779a1ae7732..fc796053c9e 100644
--- a/src/mame/video/decocass.c
+++ b/src/mame/video/decocass.c
@@ -517,6 +517,10 @@ VIDEO_START( decocass )
 	gfx_element_set_source(machine->gfx[1], decocass_charram);
 	gfx_element_set_source(machine->gfx[2], decocass_tileram);
 	gfx_element_set_source(machine->gfx[3], decocass_objectram);
+
+	/* This should ensure that the fake 17th tile is left blank
+	 * now that dirty-tile tracking is handled by the core */
+	gfx_element_decode(machine->gfx[2], 16);
 }
 
 VIDEO_UPDATE( decocass )