diff --git a/Enyim.Caching.Tests/MemcachedClientGetTests.cs b/Enyim.Caching.Tests/MemcachedClientGetTests.cs
index 61a4fe2f..e92a8321 100644
--- a/Enyim.Caching.Tests/MemcachedClientGetTests.cs
+++ b/Enyim.Caching.Tests/MemcachedClientGetTests.cs
@@ -99,17 +99,17 @@ public void When_Getting_SByte_Result_Is_Successful()
         }
 
         [Fact]
-        public async Task When_GetValueOrCreateAsync_Is_Successful()
+        public async Task GetValueOrCreateAsyncTest()
         {
-            var key = GetUniqueKey("Get");
-            var expected = "hello word";
-            var value = await _client.GetValueOrCreateAsync(key, 10, Task.FromResult(expected));
-            Assert.Equal(expected, value);
-            Assert.Equal(expected, await _client.GetValueAsync<string>(key));
-
-            key = GetUniqueKey("Get");
-            await _client.GetValueOrCreateAsync(key, 10, Task.FromResult<string>(null));
-            Assert.False((await _client.GetAsync<string>(key)).Success);
+            var key = "GetValueOrCreateAsyncTest_" + Guid.NewGuid();
+            await _client.GetValueOrCreateAsync(key, 10, () => GenerateValue());
+            var cacheValue = await _client.GetValueAsync<string>(key);
+            Assert.Equal(nameof(GetValueOrCreateAsyncTest), cacheValue);
+        }
+
+        private Task<string> GenerateValue()
+        {
+            return Task.FromResult(nameof(GetValueOrCreateAsyncTest));
         }
     }
 }
diff --git a/Enyim.Caching/Enyim.Caching.csproj b/Enyim.Caching/Enyim.Caching.csproj
index eb689dff..5a6da1e7 100755
--- a/Enyim.Caching/Enyim.Caching.csproj
+++ b/Enyim.Caching/Enyim.Caching.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <Description>EnyimMemcachedCore is a Memcached client library for .NET Core. Usage: Add services.AddEnyimMemcached(...) and app.UseEnyimMemcached() in Startup. Add IMemcachedClient into constructor.</Description>
-    <VersionPrefix>2.1.2</VersionPrefix>
+    <VersionPrefix>2.1.3</VersionPrefix>
     <Authors>cnblogs.com</Authors>
     <TargetFramework>netstandard2.0</TargetFramework>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
diff --git a/Enyim.Caching/IMemcachedClient.cs b/Enyim.Caching/IMemcachedClient.cs
index 36722599..791be93f 100644
--- a/Enyim.Caching/IMemcachedClient.cs
+++ b/Enyim.Caching/IMemcachedClient.cs
@@ -16,7 +16,7 @@ public interface IMemcachedClient : IDisposable
 
         Task<IGetOperationResult<T>> GetAsync<T>(string key);
         Task<T> GetValueAsync<T>(string key);
-        Task<T> GetValueOrCreateAsync<T>(string key, int cacheSeconds, Task<T> generator);
+        Task<T> GetValueOrCreateAsync<T>(string key, int cacheSeconds, Func<Task<T>> generator);
         object Get(string key);
         T Get<T>(string key);
         IDictionary<string, T> Get<T>(IEnumerable<string> keys);
diff --git a/Enyim.Caching/MemcachedClient.cs b/Enyim.Caching/MemcachedClient.cs
index 980ea9cd..35d59f26 100755
--- a/Enyim.Caching/MemcachedClient.cs
+++ b/Enyim.Caching/MemcachedClient.cs
@@ -219,7 +219,7 @@ public async Task<T> GetValueAsync<T>(string key)
             return result.Success ? result.Value : default(T);
         }
 
-        public async Task<T> GetValueOrCreateAsync<T>(string key, int cacheSeconds, Task<T> generator)
+        public async Task<T> GetValueOrCreateAsync<T>(string key, int cacheSeconds, Func<Task<T>> generator)
         {
             var result = await GetAsync<T>(key);
             if (result.Success)
@@ -227,7 +227,7 @@ public async Task<T> GetValueOrCreateAsync<T>(string key, int cacheSeconds, Task
                 return result.Value;
             }
 
-            var value = await generator;
+            var value = await generator?.Invoke();
             if (value != null)
             {
                 await AddAsync(key, value, cacheSeconds);
diff --git a/Enyim.Caching/NullMemcachedClient.cs b/Enyim.Caching/NullMemcachedClient.cs
index 4ffa5bdf..1cd061bb 100644
--- a/Enyim.Caching/NullMemcachedClient.cs
+++ b/Enyim.Caching/NullMemcachedClient.cs
@@ -248,9 +248,9 @@ public Task SetAsync(string key, object value, int cacheSeconds)
             return Task.CompletedTask;
         }
 
-        public Task<T> GetValueOrCreateAsync<T>(string key, int cacheSeconds, Task<T> generator)
+        public Task<T> GetValueOrCreateAsync<T>(string key, int cacheSeconds, Func<Task<T>> generator)
         {
-            return generator;
+            return generator?.Invoke();
         }
 
         public Task FlushAllAsync()