diff --git a/JSONAPI.Tests/Core/ModelManagerTests.cs b/JSONAPI.Tests/Core/ModelManagerTests.cs
index 5bbe7198..5190c462 100644
--- a/JSONAPI.Tests/Core/ModelManagerTests.cs
+++ b/JSONAPI.Tests/Core/ModelManagerTests.cs
@@ -54,11 +54,13 @@ public void GetJsonKeyForTypeTest()
             var postKey = mm.GetJsonKeyForType(typeof(Post));
             var authorKey = mm.GetJsonKeyForType(typeof(Author));
             var commentKey = mm.GetJsonKeyForType(typeof(Comment));
+            var manyCommentKey = mm.GetJsonKeyForType(typeof(Comment[]));
 
             // Assert
             Assert.AreEqual("posts", postKey);
             Assert.AreEqual("authors", authorKey);
             Assert.AreEqual("comments", commentKey);
+            Assert.AreEqual("comments", manyCommentKey);
         }
 
         [TestMethod]
diff --git a/JSONAPI/Core/ModelManager.cs b/JSONAPI/Core/ModelManager.cs
index 5dc49bcc..78724466 100644
--- a/JSONAPI/Core/ModelManager.cs
+++ b/JSONAPI/Core/ModelManager.cs
@@ -127,11 +127,11 @@ public string GetJsonKeyForType(Type type)
 
             lock (keyCache)
             {
-                if (keyCache.TryGetValue(type, out key)) return key;
-
                 if (IsSerializedAsMany(type))
                     type = GetElementType(type);
 
+                if (keyCache.TryGetValue(type, out key)) return key;
+
                 var attrs = type.CustomAttributes.Where(x => x.AttributeType == typeof(Newtonsoft.Json.JsonObjectAttribute)).ToList();
 
                 string title = type.Name;