diff --git a/src/ol/base/rectangle.js b/src/ol/base/rectangle.js
index f35768e2c8..3f88315d11 100644
--- a/src/ol/base/rectangle.js
+++ b/src/ol/base/rectangle.js
@@ -41,19 +41,6 @@ ol.Rectangle = function(minX, minY, maxX, maxY) {
 };
 
 
-/**
- * @param {ol.Rectangle} rectangle1 Rectangle.
- * @param {ol.Rectangle} rectangle2 Rectangle.
- * @return {boolean} Intersects.
- */
-ol.Rectangle.intersects = function(rectangle1, rectangle2) {
-  return rectangle1.minX <= rectangle2.maxX &&
-      rectangle1.maxX >= rectangle2.minX &&
-      rectangle1.minY <= rectangle2.maxY &&
-      rectangle1.maxY >= rectangle2.minY;
-};
-
-
 /**
  * @return {ol.Rectangle} Clone.
  */
@@ -105,6 +92,18 @@ ol.Rectangle.prototype.getWidth = function() {
 };
 
 
+/**
+ * @param {ol.Rectangle} rectangle Rectangle.
+ * @return {boolean} Intersects.
+ */
+ol.Rectangle.prototype.intersects = function(rectangle) {
+  return this.minX <= rectangle.maxX &&
+      this.maxX >= rectangle.minX &&
+      this.minY <= rectangle.maxY &&
+      this.maxY >= rectangle.minY;
+};
+
+
 /**
  * @param {ol.Coordinate} coordinate Coordinate.
  * @return {ol.Coordinate} Coordinate.
diff --git a/src/ol/base/rectangle_test.js b/src/ol/base/rectangle_test.js
index 3e5d716f1c..0eea82c85b 100644
--- a/src/ol/base/rectangle_test.js
+++ b/src/ol/base/rectangle_test.js
@@ -64,11 +64,11 @@ function testIntersects() {
 
   function assertIntersects(rectangle2) {
     assertTrue(rectangle1 + ' expected to intersect ' + rectangle2,
-        ol.Rectangle.intersects(rectangle1, rectangle2));
+        rectangle1.intersects(rectangle2));
   }
   function assertNotIntersects(rectangle2) {
     assertFalse(rectangle1 + ' expected to not intersect ' + rectangle2,
-        ol.Rectangle.intersects(rectangle1, rectangle2));
+        rectangle1.intersects(rectangle2));
   }
 
   assertIntersects(rectangle1);