diff --git a/Source/Core/VideoBackends/OGL/GLExtensions/GLExtensions.cpp b/Source/Core/VideoBackends/OGL/GLExtensions/GLExtensions.cpp
index de200343e4..75988b09c6 100644
--- a/Source/Core/VideoBackends/OGL/GLExtensions/GLExtensions.cpp
+++ b/Source/Core/VideoBackends/OGL/GLExtensions/GLExtensions.cpp
@@ -1984,7 +1984,7 @@ namespace GLExtensions
 		while (buffer >> tmp)
 		{
 			if (tmp[0] == '!')
-				result &= !m_extension_list[tmp.erase(0)];
+				result &= !m_extension_list[tmp.erase(0, 1)];
 			else
 				result &= m_extension_list[tmp];
 		}