diff --git a/src/tgba/taatgba.cc b/src/tgba/taatgba.cc
index f0c16eb02..45bbc1c3f 100644
--- a/src/tgba/taatgba.cc
+++ b/src/tgba/taatgba.cc
@@ -254,6 +254,8 @@ namespace spot
 	  && (i == seen_.end() || j == i->second.end()))
       {
 	seen_[b].push_back(t);
+	if (i != seen_.end())
+	  delete b;
 	succ_.push_back(t);
       }
       else