diff --git a/src/gallium/drivers/swr/rasterizer/core/api.cpp b/src/gallium/drivers/swr/rasterizer/core/api.cpp
index e5e9897daa2..99d3cd5bb01 100644
--- a/src/gallium/drivers/swr/rasterizer/core/api.cpp
+++ b/src/gallium/drivers/swr/rasterizer/core/api.cpp
@@ -166,7 +166,7 @@ HANDLE SwrCreateContext(
 
 #if defined(KNOB_ENABLE_AR)
     // cache the API thread event manager, for use with sim layer
-    pCreateInfo->hArEventManager = pContext->pArContext[pContext->NumWorkerThreads + 1];
+    pCreateInfo->hArEventManager = pContext->pArContext[pContext->NumWorkerThreads];
 #endif
 
     // State setup AFTER context is fully initialized