diff --git a/maven-plugin-testing-harness/src/main/java/org/apache/maven/api/plugin/testing/MojoExtension.java b/maven-plugin-testing-harness/src/main/java/org/apache/maven/api/plugin/testing/MojoExtension.java
index 268a033f..565e99d2 100644
--- a/maven-plugin-testing-harness/src/main/java/org/apache/maven/api/plugin/testing/MojoExtension.java
+++ b/maven-plugin-testing-harness/src/main/java/org/apache/maven/api/plugin/testing/MojoExtension.java
@@ -146,6 +146,11 @@ public void beforeEach(ExtensionContext context) throws Exception {
                 .map(Basedir::value)
                 .orElseGet(PlexusExtension::getBasedir);
 
+        URL resource = context.getRequiredTestClass().getResource(basedir);
+        if (resource != null) {
+            basedir = Paths.get(resource.toURI()).toString();
+        }
+
         setTestBasedir(basedir, context);
 
         PlexusContainer plexusContainer = getContainer(context);
diff --git a/maven-plugin-testing-harness/src/test/java/org/apache/maven/plugin/testing/ParametersMojoTest.java b/maven-plugin-testing-harness/src/test/java/org/apache/maven/plugin/testing/ParametersMojoTest.java
index 4b6baed4..01c286dd 100644
--- a/maven-plugin-testing-harness/src/test/java/org/apache/maven/plugin/testing/ParametersMojoTest.java
+++ b/maven-plugin-testing-harness/src/test/java/org/apache/maven/plugin/testing/ParametersMojoTest.java
@@ -116,4 +116,12 @@ void basedirInjectedWithBasedirAnnotation(ParametersMojo mojo) {
         assertEquals("i-have-a-basedir-set-by-annotation", mojo.getPlain());
         assertDoesNotThrow(mojo::execute);
     }
+
+    @Test
+    @Basedir("/projects/basedir-set-by-annotation-classpath")
+    @InjectMojo(goal = "parameters", pom = POM_DOT_XML_FILE)
+    void basedirInjectedWithBasedirFromClasspathAnnotation(ParametersMojo mojo) {
+        assertEquals("i-have-a-basedir-set-by-annotation-classpath", mojo.getPlain());
+        assertDoesNotThrow(mojo::execute);
+    }
 }
diff --git a/maven-plugin-testing-harness/src/test/projects/basedir-set-by-annotation/pom.xml b/maven-plugin-testing-harness/src/test/projects/basedir-set-by-annotation/pom.xml
index 82cb188d..dc5af5cb 100644
--- a/maven-plugin-testing-harness/src/test/projects/basedir-set-by-annotation/pom.xml
+++ b/maven-plugin-testing-harness/src/test/projects/basedir-set-by-annotation/pom.xml
@@ -33,15 +33,6 @@ under the License.
         <groupId>test</groupId>
         <artifactId>test-plugin</artifactId>
         <version>0.0.1-SNAPSHOT</version>
-        <executions>
-          <execution>
-            <id>test</id>
-            <goals>
-              <goal>test</goal>
-            </goals>
-            <phase>compile</phase>
-          </execution>
-        </executions>
         <configuration>
           <plain>i-have-a-basedir-set-by-annotation</plain>
         </configuration>
diff --git a/maven-plugin-testing-harness/src/test/resources/projects/basedir-set-by-annotation-classpath/pom.xml b/maven-plugin-testing-harness/src/test/resources/projects/basedir-set-by-annotation-classpath/pom.xml
new file mode 100644
index 00000000..0fd819e3
--- /dev/null
+++ b/maven-plugin-testing-harness/src/test/resources/projects/basedir-set-by-annotation-classpath/pom.xml
@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
+<project>
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>test</groupId>
+  <artifactId>test-test</artifactId>
+  <version>1.0-SNAPSHOT</version>
+  <packaging>jar</packaging>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>test</groupId>
+        <artifactId>test-plugin</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <configuration>
+          <plain>i-have-a-basedir-set-by-annotation-classpath</plain>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+</project>