Sinner and Medvedev reach Miami Open last eight

Australian Open champion Jannik Sinner is through to the Miami Open quarter-finals, while Daniil Medvedev also progressed with a straight-set win.

The talented 22-year-old Italian, who triumphed in his first major final in Melbourne in January, beat Australian Christopher O'Connell 6-4 6-3.

The world number three will play Czech Tomas Machac for a semi-final place.

Fourth-ranked Russian Medvedev defeated German Dominik Koepfer 7-6 (7-5) 6-0 to set up a meeting with Nicolas Jarry.

Chilean Jarry, the 22nd seed, stunned Norway's world number eight Casper Ruud 7-6 (7-3) 6-3.

Sinner fell a break of serve behind against the 66th-ranked O'Connell but he reeled off four successive games to turn around the first set before striking early in the second on his way to clinching an ultimately straightforward victory.

Upcoming opponent Machac, who ended Briton Andy Murray's hopes in the third round, beat Italy's Matteo Arnaldi 6-3 6-3.

Later on Tuesday in Miami, Spanish world number two Carlos Alcaraz - the 2022 champion - faces Italy's Lorenzo Musetti, with Bulgarian Grigor Dimitrov or Poland's Hubert Hurkacz awaiting the winner.