Sinner and Medvedev power into Miami last four

World number three Jannik Sinner will face defending champion Daniil Medvedev in the semi-finals of the Miami Open – a re-match of last year's final -- after they both enjoyed victories on Wednesday. Sinner moved into the last four in emphatic style, beating Czech Tomas Machac 6-4, 6-2 before Medvedev overcame