Rafael Nadal among withdrawals as Andy Murray survives mass exodus in Miami

Andy Murray progressed to the Miami Open third round but Saturday's play was dominated by withdrawals, including fifth seed Rafael Nadal, and a curious end to Sam Querrey's challenge.

Second seed Murray was not at his fluent best again Denis Istomin but came through 6-3 7-5 to set up an enticing third-round clash against Grigor Dimitrov, a three-set winner over Federico Delbonis.