The astronauts prepared the terrain by first unhooking all the electric lines and the ammonia fluid on the pump. NASA Mission Control sees this as "an early Christmas". If the two American astronauts keep up the good work then the installation of a new pump will be completed in just two spacewalks.
NASA originally anticipated that three space walks would be required and the third one was planned to be done on Christmas day. One of the most fright-full point of the spacewalk done on Saturday was when a small O-ring floated away from the pump. Mastracchio was the one who caught it.