diff --git a/patterns/grok-patterns b/patterns/grok-patterns
index 4f9d4229e60..2ed0045d1c0 100755
--- a/patterns/grok-patterns
+++ b/patterns/grok-patterns
@@ -68,7 +68,7 @@ SECOND (?:(?:[0-5][0-9]|60)(?:[.,][0-9]+)?)
 TIME (?!<[0-9])%{HOUR}:%{MINUTE}(?::%{SECOND})(?![0-9])
 # datestamp is YYYY/MM/DD-HH:MM:SS.UUUU (or something like it)
 DATE_US %{MONTHNUM}[/-]%{MONTHDAY}[/-]%{YEAR}
-DATE_EU %{YEAR}[/-]%{MONTHNUM}[/-]%{MONTHDAY}
+DATE_EU %{YEAR}[./-]%{MONTHNUM}[./-]%{MONTHDAY}
 ISO8601_TIMEZONE (?:Z|[+-]%{HOUR}(?::?%{MINUTE}))
 ISO8601_SECOND (?:%{SECOND}|60)
 TIMESTAMP_ISO8601 %{YEAR}-%{MONTHNUM}-%{MONTHDAY}[T ]%{HOUR}:?%{MINUTE}(?::?%{SECOND})?%{ISO8601_TIMEZONE}?