diff --git a/src/emacs/lean-mode.el b/src/emacs/lean-mode.el
index eeb3c98fd..fe9541fe0 100644
--- a/src/emacs/lean-mode.el
+++ b/src/emacs/lean-mode.el
@@ -32,7 +32,7 @@
     ("\\(λ\\|→\\|∃\\|∀\\|:\\|:=\\)" . font-lock-constant-face)
     ("\\_<\\(\\b.*_tac\\|Cond\\|or_else\\|t\\(?:hen\\|ry\\)\\|when\\|assumption\\|apply\\|b\\(?:ack\\|eta\\)\\|done\\|exact\\)\\_>" . 'font-lock-constant-face)
     ("\\_<\\(universe\\|theorem\\|axiom\\|definition\\|variable\\|parameter\\)\\_>[ \t\{\[]*\\([^ \t\n]*\\)" (2 'font-lock-function-name-face))
-    ("\\_<\\(variables\\|parameters\\)\\_>[ \t\{\[]*\\([^:]*\\)" (2 'font-lock-function-name-face))
+    ("\\_<\\(variables\\|parameters\\)\\_>[ \t\(\{\[]*\\([^:]*\\)" (2 'font-lock-function-name-face))
     ("\\(set_opaque\\|set_option\\)[ \t]*\\([^ \t\n]*\\)" (2 'font-lock-constant-face))
     ("\\_<_\\_>" . 'font-lock-preprocessor-face)
     ;;