diff --git a/src/ex_cmds.c b/src/ex_cmds.c
index daac3ae..d83dc40 100644
--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -6204,6 +6204,13 @@
 	    *d++ = *s;
 
 	    /*
+	     * If tag contains "({" or "([", tag terminates at the "(".
+	     * This is for help on functions, e.g.: abs({expr}).
+	     */
+	    if (*s == '(' && (s[1] == '{' || s[1] =='['))
+		break;
+
+	    /*
 	     * If tag starts with ', toss everything after a second '. Fixes
 	     * CTRL-] on 'option'. (would include the trailing '.').
 	     */
diff --git a/src/testdir/test_help_tagjump.vim b/src/testdir/test_help_tagjump.vim
index d1e9ad4..f486583 100644
--- a/src/testdir/test_help_tagjump.vim
+++ b/src/testdir/test_help_tagjump.vim
@@ -15,4 +15,14 @@
   call assert_equal("help", &filetype)
   call assert_true(getline('.') =~ "\\*'buflisted'\\*")
   helpclose
+
+  exec "help! abs({expr})"
+  call assert_equal("help", &filetype)
+  call assert_true(getline('.') =~ '\*abs()\*')
+  helpclose
+
+  exec "help! arglistid([{winnr}"
+  call assert_equal("help", &filetype)
+  call assert_true(getline('.') =~ '\*arglistid()\*')
+  helpclose
 endfunc
diff --git a/src/version.c b/src/version.c
index 6c94bc6..a8556a8 100644
--- a/src/version.c
+++ b/src/version.c
@@ -749,6 +749,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1728,
+/**/
     1727,
 /**/
     1726,