diff --git a/dd-java-agent/src/main/java/datadog/trace/agent/TracingAgent.java b/dd-java-agent/src/main/java/datadog/trace/agent/TracingAgent.java
index ecc51e8b0d..0d295fdb05 100644
--- a/dd-java-agent/src/main/java/datadog/trace/agent/TracingAgent.java
+++ b/dd-java-agent/src/main/java/datadog/trace/agent/TracingAgent.java
@@ -276,7 +276,8 @@ public class TracingAgent {
 
     final String logManagerProp = System.getProperty("java.util.logging.manager");
     if (logManagerProp != null) {
-      final boolean onSysClasspath = ClassLoader.getSystemResource(logManagerProp) != null;
+      final boolean onSysClasspath =
+          ClassLoader.getSystemResource(logManagerProp.replaceAll("\\.", "/") + ".class") != null;
       if (debugEnabled) {
         System.out.println("Prop - logging.manager: " + logManagerProp);
         System.out.println("logging.manager on system classpath: " + onSysClasspath);
diff --git a/dd-java-agent/src/test/java/jvmbootstraptest/LogManagerSetter.java b/dd-java-agent/src/test/java/jvmbootstraptest/LogManagerSetter.java
index e4662a64fa..038abcaca3 100644
--- a/dd-java-agent/src/test/java/jvmbootstraptest/LogManagerSetter.java
+++ b/dd-java-agent/src/test/java/jvmbootstraptest/LogManagerSetter.java
@@ -20,7 +20,9 @@ public class LogManagerSetter {
             "jmxfetch should start in premain when customlogmanager=false.");
       }
     } else if (System.getProperty("java.util.logging.manager") != null) {
-      if (ClassLoader.getSystemResource(System.getProperty("java.util.logging.manager")) == null) {
+      if (ClassLoader.getSystemResource(
+              System.getProperty("java.util.logging.manager").replaceAll("\\.", "/") + ".class")
+          == null) {
         customAssert(
             isJmxfetchStarted(),
             false,