diff --git a/packages/flutter/lib/src/material/time.dart b/packages/flutter/lib/src/material/time.dart
index f496d38bbb..33e85b94b1 100644
--- a/packages/flutter/lib/src/material/time.dart
+++ b/packages/flutter/lib/src/material/time.dart
@@ -48,21 +48,20 @@ enum DayPeriod {
 ///  * [DateTime], which represents date and time, and is subject to eras and
 ///    time zones.
 @immutable
-class TimeOfDay implements Comparable<TimeOfDay> {
+class TimeOfDay {
   /// Creates a time of day.
   ///
   /// The [hour] argument must be between 0 and 23, inclusive. The [minute]
   /// argument must be between 0 and 59, inclusive.
-  const TimeOfDay({ @required this.hour, @required this.minute })
-      : assert(hour != null && hour >= 0 && hour < hoursPerDay),
-        assert(minute != null && minute >= 0 && minute < minutesPerHour);
+  const TimeOfDay({ @required this.hour, @required this.minute });
 
   /// Creates a time of day based on the given time.
   ///
   /// The [hour] is set to the time's hour and the [minute] is set to the time's
   /// minute in the timezone of the given [DateTime].
   TimeOfDay.fromDateTime(DateTime time)
-    : this(hour: time.hour, minute: time.minute);
+    : hour = time.hour,
+      minute = time.minute;
 
   /// Creates a time of day based on the current time.
   ///
@@ -81,6 +80,8 @@ class TimeOfDay implements Comparable<TimeOfDay> {
 
   /// Returns a new TimeOfDay with the hour and/or minute replaced.
   TimeOfDay replacing({ int hour, int minute }) {
+    assert(hour == null || (hour >= 0 && hour < hoursPerDay));
+    assert(minute == null || (minute >= 0 && minute < minutesPerHour));
     return TimeOfDay(hour: hour ?? this.hour, minute: minute ?? this.minute);
   }
 
@@ -135,19 +136,6 @@ class TimeOfDay implements Comparable<TimeOfDay> {
 
     return '$TimeOfDay($hourLabel:$minuteLabel)';
   }
-
-  static int _inMinutesOf(TimeOfDay time) => minutesPerHour * time.hour + time.minute;
-
-  @override
-  int compareTo(TimeOfDay other) {
-    if (other == null) {
-      return 1;
-    }
-    if (other == this) {
-      return 0;
-    }
-    return _inMinutesOf(this).compareTo(_inMinutesOf(other));
-  }
 }
 
 /// Determines how the time picker invoked using [showTimePicker] formats and
diff --git a/packages/flutter/test/material/time_test.dart b/packages/flutter/test/material/time_test.dart
index c4fede0459..9e74ec5186 100644
--- a/packages/flutter/test/material/time_test.dart
+++ b/packages/flutter/test/material/time_test.dart
@@ -28,69 +28,4 @@ void main() {
       expect(await pumpTest(true), '07:00');
     });
   });
-
-  group('TimeOfDay', () {
-    test('assertions', () {
-      expect(() => TimeOfDay(hour: null, minute: null), throwsAssertionError);
-      expect(() => TimeOfDay(hour: null, minute: 0), throwsAssertionError);
-      expect(() => TimeOfDay(hour: 0, minute: null), throwsAssertionError);
-      expect(() => TimeOfDay(hour: -1, minute: -1), throwsAssertionError);
-      expect(() => TimeOfDay(hour: 0, minute: -1), throwsAssertionError);
-      expect(() => TimeOfDay(hour: -1, minute: 0), throwsAssertionError);
-      expect(() => TimeOfDay(hour: 24, minute: 0), throwsAssertionError);
-      expect(() => TimeOfDay(hour: 0, minute: 60), throwsAssertionError);
-    });
-
-    test('.==', () {
-      expect(const TimeOfDay(hour: 0 , minute: 0)
-          == (const TimeOfDay(hour: 0 , minute: 0)), true);
-    });
-
-    test('.replacing', () {
-      expect(
-        const TimeOfDay(hour: 23 , minute: 59).replacing(hour: 0),
-        const TimeOfDay(hour: 0 , minute: 59),
-      );
-      expect(
-        const TimeOfDay(hour: 23 , minute: 59).replacing(minute: 0),
-        const TimeOfDay(hour: 23 , minute: 0),
-      );
-    });
-
-    test('.compareTo', () {
-      expect(
-          <TimeOfDay>[
-            const TimeOfDay(hour: 12 , minute: 0),
-            const TimeOfDay(hour: 23 , minute: 59),
-            const TimeOfDay(hour: 0 , minute: 0),
-          ]..sort(),
-          <TimeOfDay>[
-            const TimeOfDay(hour: 0 , minute: 0),
-            const TimeOfDay(hour: 12 , minute: 0),
-            const TimeOfDay(hour: 23 , minute: 59),
-          ]
-      );
-
-      expect(const TimeOfDay(hour: 0 , minute: 0).compareTo(null) > 0, true);
-
-      const TimeOfDay zero = TimeOfDay(hour: 0 , minute: 0);
-      expect(zero.compareTo(zero), 0);
-
-      expect(const TimeOfDay(hour: 0 , minute: 0)
-          .compareTo(const TimeOfDay(hour: 0 , minute: 0)), 0);
-
-      expect(
-          <TimeOfDay>[
-            const TimeOfDay(hour: 0 , minute: 0),
-            const TimeOfDay(hour: 23 , minute: 59),
-            const TimeOfDay(hour: 12 , minute: 0),
-          ]..sort(),
-          <TimeOfDay>[
-            const TimeOfDay(hour: 0 , minute: 0),
-            const TimeOfDay(hour: 12 , minute: 0),
-            const TimeOfDay(hour: 23 , minute: 59),
-          ]
-      );
-    });
-  });
 }