diff --git a/src/marble_engine.rs b/src/marble_engine.rs
index 89aad50..e18c13f 100644
--- a/src/marble_engine.rs
+++ b/src/marble_engine.rs
@@ -529,6 +529,10 @@ impl Machine {
 		}
 		#[cfg(debug_assertions)]
 		{
+			self.debug_subticks.push(DebugSubTick {
+				grid: self.grid.clone(),
+				pos: None,
+			});
 			self.subtick_index = self.debug_subticks.len() - 1;
 		}
 	}