diff --git a/django/contrib/admin/static/admin/js/core.js b/django/contrib/admin/static/admin/js/core.js
index 8cd3609625..78b223701f 100644
--- a/django/contrib/admin/static/admin/js/core.js
+++ b/django/contrib/admin/static/admin/js/core.js
@@ -111,10 +111,6 @@ function findPosY(obj) {
         return this.getTwoDigitHour() + ':' + this.getTwoDigitMinute();
     };
 
-    Date.prototype.getHourMinuteSecond = function() {
-        return this.getTwoDigitHour() + ':' + this.getTwoDigitMinute() + ':' + this.getTwoDigitSecond();
-    };
-
     Date.prototype.getFullMonthName = function() {
         return typeof window.CalendarNamespace === "undefined"
             ? this.getTwoDigitMonth()
diff --git a/js_tests/admin/core.test.js b/js_tests/admin/core.test.js
index eaf882dc4b..ef6ec03998 100644
--- a/js_tests/admin/core.test.js
+++ b/js_tests/admin/core.test.js
@@ -46,11 +46,6 @@ QUnit.test('Date.getHourMinute', function(assert) {
     assert.equal(new Date(2014, 6, 1, 13, 25).getHourMinute(), '13:25', '1:25 pm is 13:25');
 });
 
-QUnit.test('Date.getHourMinuteSecond', function(assert) {
-    assert.equal(new Date(2014, 6, 1, 11, 0, 0).getHourMinuteSecond(), '11:00:00', '11:00 am is 11:00:00');
-    assert.equal(new Date(2014, 6, 1, 17, 45, 30).getHourMinuteSecond(), '17:45:30', '5:45:30 pm is 17:45:30');
-});
-
 QUnit.test('Date.strftime', function(assert) {
     var date = new Date(2014, 6, 1, 11, 0, 5);
     assert.equal(date.strftime('%Y-%m-%d %H:%M:%S'), '2014-07-01 11:00:05');