Federer -- the man Murray is hoping to eclipse in the world rankings -- as well as Spanish star Rafael Nadal, who won the Indian Wells title on his comeback from injury, have both chosen not to play at the Miami Masters.
The Spanish fourth seed -- beaten in the semifinals at Indian Wells by Djokovic's conqueror and eventual champion Ivan Ljubicic -- will next play Argentine wildcard David Nalbandian, who overcame Serbian 30th seed Viktor Troicki 6-3 4-6 6-4.