diff --git a/src/Ryujinx.Graphics.Shader/Translation/ResourceReservations.cs b/src/Ryujinx.Graphics.Shader/Translation/ResourceReservations.cs
index c89c4d0b6..b069f8216 100644
--- a/src/Ryujinx.Graphics.Shader/Translation/ResourceReservations.cs
+++ b/src/Ryujinx.Graphics.Shader/Translation/ResourceReservations.cs
@@ -120,7 +120,7 @@ namespace Ryujinx.Graphics.Shader.Translation
 
             if (vacUsage.UsesViewportIndex && gpuAccessor.QueryHostSupportsViewportIndexVertexTessellation())
             {
-                _offsets.Add(new IoDefinition(storageKind, IoVariable.VertexIndex), offset++);
+                _offsets.Add(new IoDefinition(storageKind, IoVariable.ViewportIndex), offset++);
             }
 
             if (vacUsage.UsesViewportMask && gpuAccessor.QueryHostSupportsViewportMask())