diff --git a/maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/AbstractSurefireMojo.java b/maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/AbstractSurefireMojo.java
index 7cbe8bbb2b..7c337818ad 100644
--- a/maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/AbstractSurefireMojo.java
+++ b/maven-surefire-common/src/main/java/org/apache/maven/plugin/surefire/AbstractSurefireMojo.java
@@ -2569,7 +2569,7 @@ private TestClassPath generateTestClasspath() throws MojoFailureException {
 
         Map<String, Artifact> dependencyConflictIdsProjectArtifacts = classpathArtifacts.stream()
                 .collect(Collectors.toMap(Artifact::getDependencyConflictId, Function.identity()));
-        Set<String> additionalClasspathElements = new HashSet<>();
+        Set<String> additionalClasspathElements = new LinkedHashSet<>();
         if (getAdditionalClasspathElements() != null) {
             Arrays.stream(getAdditionalClasspathElements()).forEach(additionalClasspathElements::add);
         }
diff --git a/surefire-its/src/test/java/org/apache/maven/surefire/its/AdditionalClasspathIT.java b/surefire-its/src/test/java/org/apache/maven/surefire/its/AdditionalClasspathIT.java
index 6180bd95a6..27398d6acb 100644
--- a/surefire-its/src/test/java/org/apache/maven/surefire/its/AdditionalClasspathIT.java
+++ b/surefire-its/src/test/java/org/apache/maven/surefire/its/AdditionalClasspathIT.java
@@ -30,7 +30,7 @@
 public class AdditionalClasspathIT extends SurefireJUnit4IntegrationTestCase {
     @Test
     public void additionalClasspathElements() {
-        unpack("/additional-classpath").executeTest().verifyErrorFree(1);
+        unpack("/additional-classpath").executeTest().verifyErrorFree(2);
     }
 
     @Test
diff --git a/surefire-its/src/test/resources/additional-classpath/extraResource/order-test.txt b/surefire-its/src/test/resources/additional-classpath/extraResource/order-test.txt
new file mode 100644
index 0000000000..56a6051ca2
--- /dev/null
+++ b/surefire-its/src/test/resources/additional-classpath/extraResource/order-test.txt
@@ -0,0 +1 @@
+1
\ No newline at end of file
diff --git a/surefire-its/src/test/resources/additional-classpath/extraResource2/order-test.txt b/surefire-its/src/test/resources/additional-classpath/extraResource2/order-test.txt
new file mode 100644
index 0000000000..d8263ee986
--- /dev/null
+++ b/surefire-its/src/test/resources/additional-classpath/extraResource2/order-test.txt
@@ -0,0 +1 @@
+2
\ No newline at end of file
diff --git a/surefire-its/src/test/resources/additional-classpath/src/test/java/additionalClasspath/BasicTest.java b/surefire-its/src/test/resources/additional-classpath/src/test/java/additionalClasspath/BasicTest.java
index 1cc4cad9c5..f1f5368b35 100644
--- a/surefire-its/src/test/resources/additional-classpath/src/test/java/additionalClasspath/BasicTest.java
+++ b/surefire-its/src/test/resources/additional-classpath/src/test/java/additionalClasspath/BasicTest.java
@@ -1,5 +1,12 @@
 package additionalClasspath;
 
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.net.URL;
+import java.util.Enumeration;
+
 import junit.framework.TestCase;
 
 public class BasicTest
@@ -9,7 +16,28 @@ public class BasicTest
     public void testExtraResource()
     {
         assertNotNull( BasicTest.class.getResourceAsStream( "/test.txt" ) );
+        assertNotNull( getClass().getClassLoader().getResourceAsStream( "test.txt" ) );
         assertNotNull( BasicTest.class.getResourceAsStream( "/test2.txt" ) );
+        assertNotNull( getClass().getClassLoader().getResourceAsStream( "test2.txt" ) );
     }
 
+    public void testExtraResourceOrder() throws IOException
+    {
+        Enumeration<URL> resources = getClass().getClassLoader().getResources("order-test.txt");
+        assertTrue( resources.hasMoreElements() );
+        URL url = resources.nextElement();
+        InputStream is = url.openStream();
+        assertNotNull( is );
+        try ( InputStream i = is; InputStreamReader r = new InputStreamReader(is); BufferedReader br = new BufferedReader(r) ) {
+            assertEquals("1", br.readLine());
+        }
+        assertTrue( resources.hasMoreElements() );
+        url = resources.nextElement();
+        is = url.openStream();
+        assertNotNull( is );
+        try ( InputStream i = is; InputStreamReader r = new InputStreamReader(is); BufferedReader br = new BufferedReader(r) ) {
+            assertEquals("2", br.readLine());
+        }
+        assertFalse( resources.hasMoreElements() );
+    }
 }