Blur Filter With Tween

Trying to set up a simple blur-tween to learn the process. I am missing something with the blur effect.

Any Help?

import flash.filters.*;
import mx.transitions.Tween;
import mx.transitions.easing.*;
for (var i = 0; i < 1; i++) {
 var yb:Button = (this.attachMovie ("yelBox", "yelBox", +i, i));
 this._x = 275;
 this._y = 200;
 this._xscale = 50;
 this._yscale = 25;
}
for (var i = 0; i < 1; i++) {
 yb.onRelease = function () {
  var currentx:Number = this._x;
  new Tween (this, "_width", Back.easeInOut, 100, 200, 2, true);
  new Tween (this, "_x", Back.easeInOut, currentx, 100, 2, true);
  var blur = new flash.filters.BlurFilter (10, 10, 1;
  new Tween(this, "blur", Strong.easeOut, 0, 10, 1, true);
 };
}