diff --git a/src/hb-ot-layout-gsub-table.hh b/src/hb-ot-layout-gsub-table.hh
index b10f9b6f3e7b16a6d641ba34c6238087e66f0f2b..49ada88d4d87619651bb362f0d7ce6f18a371f7b 100644
--- a/src/hb-ot-layout-gsub-table.hh
+++ b/src/hb-ot-layout-gsub-table.hh
@@ -506,6 +506,7 @@ struct Ligature
     }
     else
     {
+      c->buffer->merge_clusters (c->buffer->idx, skippy_iter.idx + 1);
       c->replace_glyph (ligGlyph);
 
       /* Now we must do a second loop to copy the skipped glyphs to