diff --git a/src/python/pants/engine/legacy/graph.py b/src/python/pants/engine/legacy/graph.py
index 4ec06df61dc6..57e44d1b3473 100644
--- a/src/python/pants/engine/legacy/graph.py
+++ b/src/python/pants/engine/legacy/graph.py
@@ -252,6 +252,9 @@ def _inject_specs(self, subjects):
 
     Yields the resulting addresses.
     """
+    if not subjects:
+      return
+
     logger.debug('Injecting specs to %s: %s', self, subjects)
     with self._resolve_context():
       specs = tuple(subjects)