Novak Djokovic Storms Into Shanghai Masters Quarter-Finals

World number one Novak Djokovic dismissed Canadian qualifier Vasek Pospisil 6-4, 6-4 to storm into the Shanghai Masters quarter-finals on Thursday.

The 12-time Grand Slam-winner came into the tournament with questions over his motivation but he left little room for doubt in a comprehensive victory.

Djokovic weathered 12 aces and 28 winners from Pospisil, 26, before completing the 79-minute victory with a searing forehand to the corner.

The Serb insists he is no longer chasing titles or rankings points after suffering a crisis of motivation since he completed a career Grand Slam at the French Open in June.

But he is now into the Shanghai last eight without dropping a set and will face 110th-ranked Mischa Zverev for a place in the semi-finals.

America's Jack Sock recovered from losing the first set to love as he beat Milos Raonic 0-6, 6-4, 7-6 (10/8), ending a run of eight straight defeats to the Canadian fifth seed.

And Jo-Wilfried Tsonga ousted racquet-smashing teenager Alexander Zverev, denying the young German a potential match-up with his elder brother, Mischa.

Zverev, 19, pushed the ninth seed all the way until he was broken for 5-6 in the third set, prompting a furious racquet-battering which earned him a warning for unsportsmanlike conduct.

Tsonga, serving for the match, safely negotiated three break points before a spectacular airborne smash set up match point, which he gobbled up to win 6-7 (4/7), 6-2, 7-5.

Zverev's brother Mischa, a decade older at 29, also went three sets against Marcel Granollers of Spain but he came out on top 6-7 (4/7), 6-4, 6-1.

The Zverevs were the first brothers since Olivier and Christophe Rochus at Miami 2006 to reach the last 16 of a Masters tournament, and were on course to meet in the semis.