diff --git a/config/src/main/java/com/typesafe/config/impl/ConfigDelayedMerge.java b/config/src/main/java/com/typesafe/config/impl/ConfigDelayedMerge.java
index <HASH>..<HASH> 100644
--- a/config/src/main/java/com/typesafe/config/impl/ConfigDelayedMerge.java
+++ b/config/src/main/java/com/typesafe/config/impl/ConfigDelayedMerge.java
@@ -270,6 +270,11 @@ final class ConfigDelayedMerge extends AbstractConfigValue implements Unmergeabl
         render(stack, sb, indent, atRoot, atKey, options);
     }
 
+    @Override
+    protected void render(StringBuilder sb, int indent, boolean atRoot, ConfigRenderOptions options) {
+        render(sb, indent, atRoot, null, options);
+    }
+
     // static method also used by ConfigDelayedMergeObject.
     static void render(List<AbstractConfigValue> stack, StringBuilder sb, int indent, boolean atRoot, String atKey,
             ConfigRenderOptions options) {
Fix toString of ConfigDelayedMerge, the default render() in superclass didn't work

The superclass called unwrapped() to render, which isn't allowed here.