diff --git a/pyproject.toml b/pyproject.toml
index 4de04cce4..956c60623 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -3,9 +3,9 @@ line-length = 99
 target-version = ['py36']
 skip-string-normalization = true
 
-# We need to force-exclude the negated include pattern so
+# We need to force-exclude the negated include pattern
 # so that pre-commit run --all-files does the correct thing
 # see https://github.com/psf/black/issues/1778
-force-exclude = '^(?!(telegram|examples|tests)/).*\.py$'
+force-exclude = '^(?!/(telegram|examples|tests)/).*\.py$'
 include = '(telegram|examples|tests)/.*\.py$'
 exclude = 'telegram/vendor'
\ No newline at end of file