diff --git a/runner.py b/runner.py
index a0683c3..f43db91 100755
--- a/runner.py
+++ b/runner.py
@@ -81,7 +81,7 @@ def main():
                         p.wait()
                     except Exception as e:
                         print(e)
-                        print('Failed running experiment: {}', experiment,
+                        print('Failed running experiment: {}'.format(experiment),
                               file=sys.stderr)
                         sys.exit(1)