diff --git a/src/com/esotericsoftware/kryo/util/DefaultGenerics.java b/src/com/esotericsoftware/kryo/util/DefaultGenerics.java
index eeb22735f..e91a851ca 100644
--- a/src/com/esotericsoftware/kryo/util/DefaultGenerics.java
+++ b/src/com/esotericsoftware/kryo/util/DefaultGenerics.java
@@ -93,8 +93,9 @@ public Class nextGenericClass () {
 
 	@Override
 	public int pushTypeVariables (GenericsHierarchy hierarchy, GenericType[] args) {
-		// Do not store type variables if hierarchy is empty or we do not have arguments for all root parameters.
-		if (hierarchy.total == 0 || hierarchy.rootTotal > args.length) return 0;
+		// Do not store type variables if hierarchy is empty, or we do not have arguments for all root parameters, or we have more
+		// arguments than the hierarchy has parameters.
+		if (hierarchy.total == 0 || hierarchy.rootTotal > args.length || args.length > hierarchy.counts.length) return 0;
 
 		int startSize = this.argumentsSize;
 
diff --git a/test-kotlin/com.esotericsoftware.kryo/LambdaTest.kt b/test-kotlin/com.esotericsoftware.kryo/SerializationTest.kt
similarity index 90%
rename from test-kotlin/com.esotericsoftware.kryo/LambdaTest.kt
rename to test-kotlin/com.esotericsoftware.kryo/SerializationTest.kt
index d6f504f31..dbd9bec5f 100644
--- a/test-kotlin/com.esotericsoftware.kryo/LambdaTest.kt
+++ b/test-kotlin/com.esotericsoftware.kryo/SerializationTest.kt
@@ -4,16 +4,12 @@ import com.esotericsoftware.kryo.io.Input
 import com.esotericsoftware.kryo.io.Output
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.Assertions.assertNotSame
-import org.junit.jupiter.api.Disabled
 import org.junit.jupiter.api.Test
 
-class LambdaTest {
-    class Example(private val p: (Long) -> String) {
-        constructor() : this({ it.toString() })
-    }
+class SerializationTest {
 
+    // https://github.com/EsotericSoftware/kryo/issues/864
     @Test
-    @Disabled("Expected to fail")
     fun testLambda() {
         val kryo = Kryo().apply {
             isRegistrationRequired = false
@@ -33,5 +29,9 @@ class LambdaTest {
         assertEquals(example::class.java, deserialized::class.java)
         assertNotSame(example, deserialized)
     }
+
+    class Example(private val p: (Long) -> String) {
+        constructor() : this({ it.toString() })
+    }
 }