diff --git a/Source/OpenTK/Platform/Windows/API.cs b/Source/OpenTK/Platform/Windows/API.cs
index db8fc961..e831d1f2 100644
--- a/Source/OpenTK/Platform/Windows/API.cs
+++ b/Source/OpenTK/Platform/Windows/API.cs
@@ -2635,13 +2635,6 @@ namespace OpenTK.Platform.Windows
     [StructLayout(LayoutKind.Sequential)]
     internal struct Win32Rectangle
     {
-        internal Win32Rectangle(int width, int height)
-        {
-            left = top = 0;
-            right = width;
-            bottom = height;
-        }
-
         /// <summary>
         /// Specifies the x-coordinate of the upper-left corner of the rectangle.
         /// </summary>
diff --git a/Source/OpenTK/Platform/Windows/WinGLNative.cs b/Source/OpenTK/Platform/Windows/WinGLNative.cs
index 61814c14..b433cb8f 100644
--- a/Source/OpenTK/Platform/Windows/WinGLNative.cs
+++ b/Source/OpenTK/Platform/Windows/WinGLNative.cs
@@ -647,10 +647,12 @@ namespace OpenTK.Platform.Windows
 
         void GrabCursor()
         {
-            Win32Rectangle rect = Win32Rectangle.From(ClientRectangle);
-            Point pos = PointToScreen(new Point(rect.left, rect.top));
+            Point pos = PointToScreen(new Point(ClientRectangle.X, ClientRectangle.Y));
+            Win32Rectangle rect = new Win32Rectangle();
             rect.left = pos.X;
+            rect.right = pos.X + ClientRectangle.Width;
             rect.top = pos.Y;
+            rect.bottom = pos.Y + ClientRectangle.Height;
             if (!Functions.ClipCursor(ref rect))
                 Debug.WriteLine(String.Format("Failed to grab cursor. Error: {0}",
                     Marshal.GetLastWin32Error()));