diff --git a/integration-tests/spring-data-jpa/pom.xml b/integration-tests/spring-data-jpa/pom.xml
index 2c7946ebe43e3..7ab4d615e16cf 100644
--- a/integration-tests/spring-data-jpa/pom.xml
+++ b/integration-tests/spring-data-jpa/pom.xml
@@ -41,6 +41,11 @@
             <artifactId>quarkus-junit5-internal</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>io.quarkus</groupId>
+            <artifactId>quarkus-junit5-mockito</artifactId>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>io.rest-assured</groupId>
             <artifactId>rest-assured</artifactId>
diff --git a/integration-tests/spring-data-jpa/src/test/java/io/quarkus/it/spring/data/jpa/PostRepositorySpyTest.java b/integration-tests/spring-data-jpa/src/test/java/io/quarkus/it/spring/data/jpa/PostRepositorySpyTest.java
new file mode 100644
index 0000000000000..22333b6453445
--- /dev/null
+++ b/integration-tests/spring-data-jpa/src/test/java/io/quarkus/it/spring/data/jpa/PostRepositorySpyTest.java
@@ -0,0 +1,26 @@
+package io.quarkus.it.spring.data.jpa;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.verify;
+
+import org.junit.jupiter.api.Test;
+
+import io.quarkus.test.junit.QuarkusTest;
+import io.quarkus.test.junit.mockito.InjectSpy;
+
+@QuarkusTest
+public class PostRepositorySpyTest {
+
+    // Without delegate = true, the call to the spy will fail with:
+    // "Cannot call abstract real method on java object!"
+    @InjectSpy(delegate = true)
+    PostRepository repo;
+
+    @Test
+    void testDefaultMethodOfIntermediateRepositoryInSpy() {
+        doReturn(new Post()).when(repo).findMandatoryById(1111L);
+        assertNotNull(repo.findMandatoryById(1111L));
+        verify(repo).findMandatoryById(1111L);
+    }
+}
diff --git a/test-framework/junit5-mockito/src/main/java/io/quarkus/test/junit/mockito/InjectSpy.java b/test-framework/junit5-mockito/src/main/java/io/quarkus/test/junit/mockito/InjectSpy.java
index d21d9f3e3bcb0..0bad87a8a2666 100644
--- a/test-framework/junit5-mockito/src/main/java/io/quarkus/test/junit/mockito/InjectSpy.java
+++ b/test-framework/junit5-mockito/src/main/java/io/quarkus/test/junit/mockito/InjectSpy.java
@@ -12,4 +12,15 @@
 @Target(ElementType.FIELD)
 @Retention(RetentionPolicy.RUNTIME)
 public @interface InjectSpy {
+
+    /**
+     * {@code true} will create a mock that <em>delegates</em> all calls to the real bean, instead of creating a regular Mockito
+     * spy.
+     * <p/>
+     * You should try this mode when you get errors like "Cannot call abstract real method on java object!" when calling a
+     * {@code default} interface method of a spied bean.
+     *
+     * @see org.mockito.AdditionalAnswers#delegatesTo(Object)
+     */
+    boolean delegate() default false;
 }
diff --git a/test-framework/junit5-mockito/src/main/java/io/quarkus/test/junit/mockito/internal/CreateMockitoSpiesCallback.java b/test-framework/junit5-mockito/src/main/java/io/quarkus/test/junit/mockito/internal/CreateMockitoSpiesCallback.java
index b292e0d18700a..c4a62cc5143cd 100644
--- a/test-framework/junit5-mockito/src/main/java/io/quarkus/test/junit/mockito/internal/CreateMockitoSpiesCallback.java
+++ b/test-framework/junit5-mockito/src/main/java/io/quarkus/test/junit/mockito/internal/CreateMockitoSpiesCallback.java
@@ -2,6 +2,7 @@
 
 import java.lang.reflect.Field;
 
+import org.mockito.AdditionalAnswers;
 import org.mockito.Mockito;
 
 import io.quarkus.arc.runtime.ClientProxyUnwrapper;
@@ -18,7 +19,7 @@ public void afterConstruct(Object testInstance) {
                 InjectSpy injectSpyAnnotation = field.getAnnotation(InjectSpy.class);
                 if (injectSpyAnnotation != null) {
                     Object beanInstance = CreateMockitoMocksCallback.getBeanInstance(testInstance, field, InjectSpy.class);
-                    Object spy = createSpyAndSetTestField(testInstance, field, beanInstance);
+                    Object spy = createSpyAndSetTestField(testInstance, field, beanInstance, injectSpyAnnotation.delegate());
                     MockitoMocksTracker.track(testInstance, spy, beanInstance);
                 }
             }
@@ -26,9 +27,10 @@ public void afterConstruct(Object testInstance) {
         }
     }
 
-    private Object createSpyAndSetTestField(Object testInstance, Field field, Object beanInstance) {
-        ClientProxyUnwrapper unwrapper = new ClientProxyUnwrapper();
-        Object spy = Mockito.spy(unwrapper.apply(beanInstance));
+    private Object createSpyAndSetTestField(Object testInstance, Field field, Object beanInstance, boolean delegate) {
+        Object unwrapped = new ClientProxyUnwrapper().apply(beanInstance);
+        Object spy = delegate ? Mockito.mock(unwrapped.getClass(), AdditionalAnswers.delegatesTo(unwrapped))
+                : Mockito.spy(unwrapped);
         field.setAccessible(true);
         try {
             field.set(testInstance, spy);