the big one martin del paco. —— he beat one martin del paco. —— he beat one martin del paco. —— he beatl potro. the swiss who's already won the australian open and indian wells masters tournaments this year was rarely troubled against del potro, and will play spain's roberto bautista agut in the round of 16 as he searches for a third title at this event and first since 2006. not so simple for 12th seed nick kyrgios though. the australian needed nearly two and a half hours to get the better of croatia's ivo karlovic taking it 6—4, 6—7, 7—6 to set up a last 16 match against either david goffin or diego schwartzman. czech number 10 seed tomas berdych is into the fourth round after he saw off the challenge of luxembourg's gilles muller, winning in straight sets 6—3, 6—4 and will next play france's adrian mannarino. andy murray was meant to be playing in miami but had to withdraw because of injury. he's now unlikely to be fit for great britain's davis cup tie against france next week. his brotherjamie has revealed that the world number one has a tear in his elbow and needs rest. we already k