The 37-year-old will next face Croatian power-hitter Borna Coric, who dumped Australia's Matthew Ebden out of the tournament 7-5 6-4.
Cape Town - Serbia's Novak Djokovic reached the Shanghai Masters semi-finals after beating South Africa's Kevin Anderson in straight sets on Friday.
"I knew I had to step it up too, and I was able to do it, so it's a good feeling to have, no doubt about it".
Djokovic held the advantage to seal the victory and set up a semi-final clash with Germany's Alexander Zverev, who became the fifth singles player to qualify for November's ATP Finals with a 6-4 6-4 win over Kyle Edmund.
A sublime backhand pass followed by a forehand victor sealed a break to love for Zverev in the fifth game of the second set, and he duly wrapped up victory with minimal fuss.
The 20-times Grand Slam victor has produced a series of lacklustre performances in Shanghai, his first tournament since suffering a shock fourth-round defeat by John Millman at the U.S. Open last month.
The second seed is desperate to grab injured Rafael Nadal's year-end number one ranking.
Djokovic, who has won the last two Grand Slams, at Wimbledon and the U.S. Open, is now world number three, but could move up a spot if he books a place in Sunday's final.
Djokovic, who endured a turbulent last season with injury and off-court issues, said they were "both different players" now. "It's going to be definitely a close match".
He will jump a spot to No 2 in the world if he reaches the final in Shanghai.
The top four players in the world - Nadal, Federer, Djokovic and Juan Martin del Potro - had already qualified for London.
The third-ranked Djokovic taught Zverev a lesson.
About his co-operation with Ivan Lendl, Zverev added: 'We are still working together.
"It means a lot because I have kind of played only the biggest tournaments", Zverev said.
'There is a lot going on you don't get to see on the inside but most of the time I learn to control the emotions'.
"It's always easier to get there - but then staying there is always the tougher part".
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It's very rare and typically affects the nervous system, specifically the spinal cord which could lead to paralysis in some cases. Though the CDC says it's not necessarily proven to guard against AFM, they recommend frequent hand-washing with soap and water.
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He added that they have been playing well and further told that they are very aware of Sri Lanka's quality in home conditions. Morgan's leadership has been instrumental in England's rise from World Cup also-rans in 2015 to the world No 1 spot.
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About 285 people defied mandatory evacuation orders in Mexico Beach . "It's insane. FEMA used dogs, drones, and Global Positioning System in the search.