Juan Martin del Potro edged closer to a spot at next month's ATP Finals after dispatching qualifier Julien Benneteau to reach the Swiss Indoors quarter-finals in Basel on Thursday.
The fourth seed, who won the Basel title in 2012 and 2013, came through in straight sets against Frenchman Benneteau 6-4 6-4.
The Argentine is 14th in the standings for the Race To London with only two weeks remaining to the eight-man season-ending tournament in London.
But with Andy Murray not in action, and Novak Djokovic and Stan Wawrinka out for the rest of the season due to injury, the South American's position is looking stronger and stronger.
Del Potro went into the Basel tournament 470 points adrift of Pablo Carreno Busta in the final qualifying place, with 500 points on offer in Basel before the final Masters 1000 event of the season next week in Paris.
And with Spaniard Carreno Busta losing 5-7 6-1 6-1 to Diego Schwartzman at the Erste Bank Open in Vienna on the same day, Del Potro received a timely boost ahead of his last-eight match against Roberto Bautista Agut.
"I'm tired, but I'm still winning and playing good tennis," the world No 19 said. "This keeps me motivated to keep going. I have good chances to go far here and also rise in the rankings. I face a tough opponent tomorrow, so we will see what will happen.
"I played better than yesterday, but tomorrow I need to improve a little bit more. Bautista is one of the toughest guys, it will be a high-level match."
Del Potro has been on a good run of form in recent weeks, reaching the Shanghai Masters semi-finals and winning the Stockholm title last weekend.
Sky Sports will have all the action from the Erste Bank Open in Vienna and Swiss Indoors Basel before the Paris Masters.
The Next Gen ATP Finals in Milan and season-ending extravaganza ATP Finals at London's O2 in November end another memorable year which will be covered via our website sky.mnosports.com/tennis with live blogs and updates as the season reaches its climax.
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