diff --git a/src/p_tags.cpp b/src/p_tags.cpp
index c08caec8fb..99796e2691 100644
--- a/src/p_tags.cpp
+++ b/src/p_tags.cpp
@@ -98,7 +98,7 @@ void FTagManager::AddSectorTag(int sector, int tag)
 
 void FTagManager::RemoveSectorTags(int sect)
 {
-	if (startForSector.Size() > 0)
+	if (startForSector.Size() > sect)
 	{
 		int start = startForSector[sect];
 		if (start >= 0)