UPDATE 3-Tennis-Rafa, Roger through in Madrid, Murray falls

* Nadal repels plucky Verdasco

* Federer thwarts Roddick fightback

* Del Potro too good for birthday boy Murray

* Djokovic sees off wildcard Ljubicic

(Adds Murray result, Nadal quotes)

By Iain Rogers

MADRID, May 15 (Reuters) - World number one Rafael Nadal survived a second-set scare to beat Spanish compatriot Fernando Verdasco 6-4 7-5 and seal his place in the semi-finals of the Madrid Open on Friday.

Nadal will play Novak Djokovic for a place in Sunday's final after the Serbian third seed stayed on course for a fifth straight final appearance with a 6-4 6-4 win over Croatian wildcard Ivan Ljubicic.