diff --git a/Assets/Scripts/Blood/BloodComputeShader.cs b/Assets/Scripts/Blood/BloodComputeShader.cs
index a26d038..2e3b021 100644
--- a/Assets/Scripts/Blood/BloodComputeShader.cs
+++ b/Assets/Scripts/Blood/BloodComputeShader.cs
@@ -3,6 +3,7 @@ using System.Collections;
 using System.Collections.Generic;
 using ComputeShaderUtility;
 using UnityEngine;
+using UnityEngine.Assertions;
 using UnityEngine.Rendering;
 
 public struct Droplet
@@ -61,6 +62,8 @@ public class BloodComputeShader : MonoBehaviour
     [SerializeField]
     uint bufferLookPointer = 0;
 
+    private bool gameHasStarted = false;
+
     private void Awake()
     {
         if (Instance != null)
@@ -137,12 +140,17 @@ public class BloodComputeShader : MonoBehaviour
     {
         mop1 = players[0].GetComponent<Mop>();
         mop2 = players[1].GetComponent<Mop>();
+
+        gameHasStarted = true;
     }
 
     // Update is called once per frame
     void Update()
     {
-        if (mop1 == null || mop2 == null) return;
+        if (!gameHasStarted) return;
+
+        Assert.IsNotNull(mop1);
+        Assert.IsNotNull(mop2);
 
         bloodCompute.SetFloat("deltaTime", Time.deltaTime);
         bloodCompute.SetInt("numParticles", numParticles);