diff --git a/src/ImageSharp/IO/BufferedReadStream.cs b/src/ImageSharp/IO/BufferedReadStream.cs
index dfc05e62fa..ae733a88ed 100644
--- a/src/ImageSharp/IO/BufferedReadStream.cs
+++ b/src/ImageSharp/IO/BufferedReadStream.cs
@@ -21,8 +21,6 @@ namespace SixLabors.ImageSharp.IO
 
         private const int MaxBufferIndex = BufferLength - 1;
 
-        private readonly Stream stream;
-
         private readonly byte[] readBuffer;
 
         private MemoryHandle readBufferHandle;
@@ -54,7 +52,7 @@ namespace SixLabors.ImageSharp.IO
                 stream.Flush();
             }
 
-            this.stream = stream;
+            this.BaseStream = stream;
             this.Position = (int)stream.Position;
             this.Length = stream.Length;
 
@@ -88,7 +86,7 @@ namespace SixLabors.ImageSharp.IO
                 else
                 {
                     // Base stream seek will throw for us if invalid.
-                    this.stream.Seek(value, SeekOrigin.Begin);
+                    this.BaseStream.Seek(value, SeekOrigin.Begin);
                     this.readerPosition = value;
                     this.readBufferIndex = BufferLength;
                 }
@@ -104,6 +102,15 @@ namespace SixLabors.ImageSharp.IO
         /// <inheritdoc/>
         public override bool CanWrite { get; } = false;
 
+        /// <summary>
+        /// Gets the underlying stream.
+        /// </summary>
+        public Stream BaseStream
+        {
+            [MethodImpl(MethodImplOptions.AggressiveInlining)]
+            get;
+        }
+
         /// <inheritdoc/>
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public override int ReadByte()
@@ -148,10 +155,10 @@ namespace SixLabors.ImageSharp.IO
         public override void Flush()
         {
             // Reset the stream position to match reader position.
-            if (this.readerPosition != this.stream.Position)
+            if (this.readerPosition != this.BaseStream.Position)
             {
-                this.stream.Seek(this.readerPosition, SeekOrigin.Begin);
-                this.readerPosition = (int)this.stream.Position;
+                this.BaseStream.Seek(this.readerPosition, SeekOrigin.Begin);
+                this.readerPosition = (int)this.BaseStream.Position;
             }
 
             // Reset to trigger full read on next attempt.
@@ -218,9 +225,9 @@ namespace SixLabors.ImageSharp.IO
         [MethodImpl(MethodImplOptions.NoInlining)]
         private void FillReadBuffer()
         {
-            if (this.readerPosition != this.stream.Position)
+            if (this.readerPosition != this.BaseStream.Position)
             {
-                this.stream.Seek(this.readerPosition, SeekOrigin.Begin);
+                this.BaseStream.Seek(this.readerPosition, SeekOrigin.Begin);
             }
 
             // Read doesn't always guarantee the full returned length so read a byte
@@ -229,7 +236,7 @@ namespace SixLabors.ImageSharp.IO
             int i;
             do
             {
-                i = this.stream.Read(this.readBuffer, n, BufferLength - n);
+                i = this.BaseStream.Read(this.readBuffer, n, BufferLength - n);
                 n += i;
             }
             while (n < BufferLength && i > 0);
@@ -262,9 +269,9 @@ namespace SixLabors.ImageSharp.IO
         private int ReadToBufferDirectSlow(byte[] buffer, int offset, int count)
         {
             // Read to target but don't copy to our read buffer.
-            if (this.readerPosition != this.stream.Position)
+            if (this.readerPosition != this.BaseStream.Position)
             {
-                this.stream.Seek(this.readerPosition, SeekOrigin.Begin);
+                this.BaseStream.Seek(this.readerPosition, SeekOrigin.Begin);
             }
 
             // Read doesn't always guarantee the full returned length so read a byte
@@ -273,7 +280,7 @@ namespace SixLabors.ImageSharp.IO
             int i;
             do
             {
-                i = this.stream.Read(buffer, n, count - n);
+                i = this.BaseStream.Read(buffer, n, count - n);
                 n += i;
             }
             while (n < count && i > 0);
diff --git a/tests/ImageSharp.Tests/Image/ImageTests.Load_FileSystemPath_PassLocalConfiguration.cs b/tests/ImageSharp.Tests/Image/ImageTests.Load_FileSystemPath_PassLocalConfiguration.cs
index ed355364a3..813c68d4cf 100644
--- a/tests/ImageSharp.Tests/Image/ImageTests.Load_FileSystemPath_PassLocalConfiguration.cs
+++ b/tests/ImageSharp.Tests/Image/ImageTests.Load_FileSystemPath_PassLocalConfiguration.cs
@@ -2,8 +2,10 @@
 // Licensed under the Apache License, Version 2.0.
 
 using System;
-
+using System.IO;
+using Moq;
 using SixLabors.ImageSharp.Formats;
+using SixLabors.ImageSharp.IO;
 using SixLabors.ImageSharp.PixelFormats;
 
 using Xunit;
@@ -36,22 +38,29 @@ namespace SixLabors.ImageSharp.Tests
                 this.TestFormat.VerifyAgnosticDecodeCall(this.Marker, this.TopLevelConfiguration);
             }
 
-            [Fact(Skip = "TODO: Enable when someone tells me how this mocking stuff works.")]
+            [Fact]
             public void Configuration_Path_Decoder_Specific()
             {
                 var img = Image.Load<Rgba32>(this.TopLevelConfiguration, this.MockFilePath, this.localDecoder.Object);
 
                 Assert.NotNull(img);
-                this.localDecoder.Verify(x => x.Decode<Rgba32>(this.TopLevelConfiguration, this.DataStream));
+                this.localDecoder
+                    .Verify(
+                    x => x.Decode<Rgba32>(
+                        this.TopLevelConfiguration,
+                        It.Is<Stream>(x => ((BufferedReadStream)x).BaseStream == this.DataStream)));
             }
 
-            [Fact(Skip = "TODO: Enable when someone tells me how this mocking stuff works.")]
+            [Fact]
             public void Configuration_Path_Decoder_Agnostic()
             {
                 var img = Image.Load(this.TopLevelConfiguration, this.MockFilePath, this.localDecoder.Object);
 
                 Assert.NotNull(img);
-                this.localDecoder.Verify(x => x.Decode(this.TopLevelConfiguration, this.DataStream));
+                this.localDecoder.Verify(
+                    x => x.Decode(
+                        this.TopLevelConfiguration,
+                        It.Is<Stream>(x => ((BufferedReadStream)x).BaseStream == this.DataStream)));
             }
 
             [Fact]
diff --git a/tests/ImageSharp.Tests/Image/ImageTests.Load_FromStream_PassLocalConfiguration.cs b/tests/ImageSharp.Tests/Image/ImageTests.Load_FromStream_PassLocalConfiguration.cs
index 149a6e4732..aa3d50eae2 100644
--- a/tests/ImageSharp.Tests/Image/ImageTests.Load_FromStream_PassLocalConfiguration.cs
+++ b/tests/ImageSharp.Tests/Image/ImageTests.Load_FromStream_PassLocalConfiguration.cs
@@ -2,7 +2,7 @@
 // Licensed under the Apache License, Version 2.0.
 
 using System.IO;
-
+using Moq;
 using SixLabors.ImageSharp.Formats;
 using SixLabors.ImageSharp.IO;
 using SixLabors.ImageSharp.PixelFormats;
@@ -48,24 +48,30 @@ namespace SixLabors.ImageSharp.Tests
                 this.TestFormat.VerifySpecificDecodeCall<Rgba32>(this.Marker, this.TopLevelConfiguration);
             }
 
-            [Fact(Skip = "TODO: Enable when someone tells me how this mocking stuff works.")]
+            [Fact]
             public void Configuration_Stream_Decoder_Specific()
             {
                 var stream = new MemoryStream();
                 var img = Image.Load<Rgba32>(this.TopLevelConfiguration, stream, this.localDecoder.Object);
 
                 Assert.NotNull(img);
-                this.localDecoder.Verify(x => x.Decode<Rgba32>(this.TopLevelConfiguration, stream));
+                this.localDecoder.Verify(
+                    x => x.Decode<Rgba32>(
+                        this.TopLevelConfiguration,
+                        It.Is<Stream>(x => ((BufferedReadStream)x).BaseStream == stream)));
             }
 
-            [Fact(Skip = "TODO: Enable when someone tells me how this mocking stuff works.")]
+            [Fact]
             public void Configuration_Stream_Decoder_Agnostic()
             {
                 var stream = new MemoryStream();
                 var img = Image.Load(this.TopLevelConfiguration, stream, this.localDecoder.Object);
 
                 Assert.NotNull(img);
-                this.localDecoder.Verify(x => x.Decode(this.TopLevelConfiguration, stream));
+                this.localDecoder.Verify(
+                    x => x.Decode(
+                        this.TopLevelConfiguration,
+                        It.Is<Stream>(x => ((BufferedReadStream)x).BaseStream == stream)));
             }
 
             [Fact]