Updated builds.

build/three.js

@@ -14196,6 +14196,8 @@
 
 		intersectsSprite: function ( sprite ) {
 
+			if ( _sphere === undefined ) _sphere = new Sphere();
+
 			_sphere.center.set( 0, 0, 0 );
 			_sphere.radius = 0.7071067811865476;
 			_sphere.applyMatrix4( sprite.matrixWorld );

build/three.module.js

@@ -14190,6 +14190,8 @@ Object.assign( Frustum.prototype, {
 
 	intersectsSprite: function ( sprite ) {
 
+		if ( _sphere === undefined ) _sphere = new Sphere();
+
 		_sphere.center.set( 0, 0, 0 );
 		_sphere.radius = 0.7071067811865476;
 		_sphere.applyMatrix4( sprite.matrixWorld );