diff --git a/modules/drivers/googleanalytics/src/metabase/driver/googleanalytics/query_processor.clj b/modules/drivers/googleanalytics/src/metabase/driver/googleanalytics/query_processor.clj
index 689241192462da955beca07f02d6396a72af8e74..2249665ea03eb63bd73e7b033ad09678f2d60c85 100644
--- a/modules/drivers/googleanalytics/src/metabase/driver/googleanalytics/query_processor.clj
+++ b/modules/drivers/googleanalytics/src/metabase/driver/googleanalytics/query_processor.clj
@@ -50,7 +50,9 @@
     (and (= unit :day) (= amount 0))  "today"
     (and (= unit :day) (= amount -1)) "yesterday"
     (and (= unit :day) (< amount -1)) (str (- amount) "daysAgo")
-    :else                             (du/format-date "yyyy-MM-dd" (du/date-trunc unit (du/relative-date unit amount)))))
+    :else                             (du/format-date
+                                        "yyyy-MM-dd"
+                                        (du/date-trunc unit (du/relative-date unit amount)))))
 
 (defmethod ->rvalue :value [[_ value _]]
   value)
@@ -257,6 +259,18 @@
     [(_ :guard #{:< :> :<= :>= :between :=}) [(_ :guard (partial not= :datetime-field)) & _] & _]
     nil))
 
+(defn- normalize-unit [unit]
+  (if (= unit :default) :day unit))
+
+(defn- normalize-datetime-units
+  "Replace all unsupported datetime units with the default"
+  [filter-clause]
+  (mbql.u/replace filter-clause
+
+    [:datetime-field field unit]        [:datetime-field field (normalize-unit unit)]
+    [:absolute-datetime timestamp unit] [:absolute-datetime timestamp (normalize-unit unit)]
+    [:relative-datetime amount unit]    [:relative-datetime amount (normalize-unit unit)]))
+
 (defn- add-start-end-dates [filter-clause]
   (merge {:start-date earliest-date, :end-date latest-date} filter-clause))
 
@@ -265,7 +279,10 @@
   `handle-builtin-segment` logic)."
   [{filter-clause :filter}]
   (or (when filter-clause
-        (add-start-end-dates (parse-filter:interval (remove-non-datetime-filter-clauses filter-clause))))
+        (add-start-end-dates
+          (parse-filter:interval
+            (normalize-datetime-units
+              (remove-non-datetime-filter-clauses filter-clause)))))
       {:start-date earliest-date, :end-date latest-date}))
 
 
diff --git a/modules/drivers/googleanalytics/test/metabase/driver/googleanalytics_test.clj b/modules/drivers/googleanalytics/test/metabase/driver/googleanalytics_test.clj
index e4d000e85460ad5687e2bb3ab1c4e72cec2ac976..9cd9b7b5e598fe80b0d129b33d665c038dc115d1 100644
--- a/modules/drivers/googleanalytics/test/metabase/driver/googleanalytics_test.clj
+++ b/modules/drivers/googleanalytics/test/metabase/driver/googleanalytics_test.clj
@@ -17,8 +17,7 @@
             [metabase.test.util :as tu]
             [metabase.util.date :as du]
             [toucan.db :as db]
-            [toucan.util.test :as tt]
-            [clj-time.core :as t]))
+            [toucan.util.test :as tt]))
 
 ;;; +----------------------------------------------------------------------------------------------------------------+
 ;;; |                                        MBQL->NATIVE (QUERY -> GA QUERY)                                        |
@@ -88,7 +87,7 @@
   (ga-query {:start-date "2016-11-08", :end-date "2016-11-08"})
   (mbql->native {:query {:filter [:= (ga-date-field :day) [:absolute-datetime #inst "2016-11-08" :day]]}}))
 
-;; tests day-off correction for gt/lt operators (GA doesn't support exclusive ranges)
+;; tests off by one day correction for gt/lt operators (GA doesn't support exclusive ranges)
 (expect
   (ga-query {:start-date "2016-11-09", :end-date "today"})
   (mbql->native {:query {:filter [:> (ga-date-field :day) [:absolute-datetime #inst "2016-11-08" :day]]}}))
@@ -154,6 +153,7 @@
              :end-date   "today"})
   (mbql->native {:query {:filter [:>= (ga-date-field :day) [:relative-datetime -30 :day]]}}))
 
+;; last year excluding the first day of the range
 (expect
   (ga-query {:start-date (du/format-date "yyyy-MM-dd" (du/relative-date :day 1 (du/date-trunc :year (du/relative-date :year -1))))
              :end-date   "today"})