diff --git a/andy/src/main/java/nl/tudelft/cse1110/andy/execution/step/ReplaceClassloaderStep.java b/andy/src/main/java/nl/tudelft/cse1110/andy/execution/step/ReplaceClassloaderStep.java
index e427cf10..0dd65d22 100644
--- a/andy/src/main/java/nl/tudelft/cse1110/andy/execution/step/ReplaceClassloaderStep.java
+++ b/andy/src/main/java/nl/tudelft/cse1110/andy/execution/step/ReplaceClassloaderStep.java
@@ -4,13 +4,16 @@
 import nl.tudelft.cse1110.andy.config.DirectoryConfiguration;
 import nl.tudelft.cse1110.andy.execution.ExecutionStep;
 import nl.tudelft.cse1110.andy.result.ResultBuilder;
+import org.objenesis.ObjenesisStd;
 
+import java.lang.reflect.Field;
 import java.net.URL;
 import java.net.URLClassLoader;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Arrays;
 import java.util.List;
+import java.util.concurrent.ConcurrentHashMap;
 
 /**
  * This step replaces the classloader with one that sees the folder
@@ -26,6 +29,7 @@ public void execute(Context ctx, ResultBuilder result) {
             String pathToAddToClassloader = dirCfg.getWorkingDir();
             replaceClassloader(ctx, pathToAddToClassloader);
             ctx.setClassloaderWithStudentsCode(Thread.currentThread().getContextClassLoader());
+            clearMockitoObjenesisInstantiatorCache();
         } catch (Exception e) {
             result.genericFailure(this, e);
         }
@@ -40,6 +44,27 @@ private void replaceClassloader(Context ctx, String pathToAddToClassloader) {
         Thread.currentThread().setContextClassLoader(customClassLoader);
     }
 
+    private void clearMockitoObjenesisInstantiatorCache() throws ReflectiveOperationException {
+            Class<?> defaultInstantiatorProviderClass = Class.forName(
+                    "org.mockito.internal.creation.instance.DefaultInstantiatorProvider");
+            Field objenesisInstantiatorField = defaultInstantiatorProviderClass.getDeclaredField("INSTANCE");
+            objenesisInstantiatorField.setAccessible(true);
+
+            // org.mockito.internal.creation.instance.ObjenesisInstantiator
+            Object objenesisInstantiator = objenesisInstantiatorField.get(null);
+            Field objenesisStdField = objenesisInstantiator.getClass().getDeclaredField("objenesis");
+            objenesisStdField.setAccessible(true);
+
+            // org.objenesis.ObjenesisStd extends ObjenesisBase
+            ObjenesisStd objenesisStd = (ObjenesisStd) objenesisStdField.get(objenesisInstantiator);
+            Field objenesisBaseCacheField = objenesisStd.getClass().getSuperclass().getDeclaredField("cache");
+            objenesisBaseCacheField.setAccessible(true);
+
+            // clear instantiator cache
+            ConcurrentHashMap<?, ?> cache = (ConcurrentHashMap<?, ?>) objenesisBaseCacheField.get(objenesisStd);
+            cache.clear();
+    }
+
     private URL toURL(Path path) {
         try {
             return path.toUri().toURL();