Zverev and Kyrgios serve warnings

As expected,  the highlights on the second Monday of the Miami Open centred on two men's third round matches.

Yes Federer played del Potro and great expectations surrounded that clash.  However it was one way traffic, with the Argentine unable to crack the Swiss serve, Federer easing to a straight sets victory.

It was John Isner v Alexander Zverev and Ivo Karlovic v Nick Kyrgios that excited the South Florida crowds.

Isner served 28 aces throughout his match and he and Zverev had their serves broken only once each, both in the opening set.

Three tie breaks decided the contest, incredible serving a consistent feature.

Isner won the opening set but it was the young German who bounced back to claim the second and third tie breakers and earn a fourth round meeting with top seed Stan Wawrinka.  Stan cruised through his third round match with unseeded Malek Jaziri, winning 82% of points on his first serve.

Nick Kyrgios defeated Ivo Karlovic in three sets, and the statistics are imposing.  Always difficult to break the Croatian serve, Kyrgios managed to convert one of two chances in the first set.  Meanwhile he won all but one point on his own first serve.

Karlovic frustrated the Australian in set two, saving seven break points, and sending it to a tie break. Despite being in control for the most part, Kyrgios lost focus in the tie break and Karlovic levelled the match.

The deciding set was dominated by the serve again, and this time the tie break was all Kyrgios, seven points to two.

Kyrgios won 6-4 6-7 7-6, a tight scoreline, but he created opportunities that should have made the win somewhat easier.

92% of points won on first serve. 68% won on second serve.  9 break points on the Karlovic serve, only one converted.  

Next up is a round of sixteen clash with 8th seed David Goffin.

The women's quarter finalists have been decided, with the top three seeds leading the charge.  Angie Kerber, Karolina Pliskova and Simona Halep are joined by Johanna Konta, Venus Williams (winner over 7th seed Kuznetsova), Caroline Wozniacki (winner over 6th seed Muguruza who retired ill), Lucie Safarova (winner over 4th seed Cibulkova) and Mirjana Lucic-Baroni.