diff --git a/mode/r/r.js b/mode/r/r.js
index 6feeb11f83..de34c201bd 100644
--- a/mode/r/r.js
+++ b/mode/r/r.js
@@ -54,7 +54,7 @@ CodeMirror.defineMode("r", function(config) {
     } else if (ch == "`") {
       stream.match(/[^`]+`/);
       return "variable-3";
-    } else if (ch == "." && stream.match(/.[.\d]+/)) {
+    } else if (ch == "." && stream.match(/.(?:[.]|\d+)/)) {
       return "keyword";
     } else if (/[a-zA-Z\.]/.test(ch)) {
       stream.eatWhile(/[\w\.]/);