Top seed Stanislas Wawrinka opened his campaign in the new season with a 6-1, 6-4 demolition of teenager Borna Coric of Croatia to cruise into the ATP Chennai Open quarter-finals on Wednesday.
The Swiss world number four gave the 18-year-old Coric a tennis lesson as he began the defence of his title in the $450,000 event on the centre court of the Numgambakkam Tennis Centre.
Wawrinka, who was among the top four seeds given a bye into the second round, showed no signs of rustiness against the 95th-ranked Croatian, the youngest player in the top 100.
Wawrinka ran up a 5-0 lead in the first set and broke Coric in the seventh game of the second set to win, but not before he had wasted four match points with lazy returns from the baseline.
"I am really happy to start this way," said Wawrinka, who will defend his Australian Open title later in the month.
"I played a solid, aggressive match. I made him run around and my backhand worked well. This is a good sign and very satisfying.
"For sure Coric is a good player. He is young and has already made his mark. It was not easy out there. That is why I am happy with the way I played today."
Wawrinka will next play eighth seed Gilles Muller of Luxembourg for a place in the semi-finals.
- Muller seeks first title -
Muller, 31, still looking for his first title after 14 years on the circuit, brushed aside Swedish teenager Elias Ymer 6-4, 6-2 in an hour and 19 minutes.
Muller wrapped up the first set with a break in the 10th game and then broke the 18-year-old Ymer again in the sixth game of the second set to clinch victory.
"I think I played a good match," said Muller. "I was in control and did not allow him many openings. It's nice to start the year this way."
Fourth seed David Goffin of Belgium overcame a mid-match loss of form to struggle past Richardas Berankis of Lithuania in three sets 6-0, 4-6, 7-6 (7/1).
Having romped through the first set in 16 minutes, Goffin suddenly began making unforced errors from the baseline and served erratically to allow Berankis to draw level.
The 22nd-ranked Goffin failed to hold his serve while serving for the match at 5-3 in the decider, but played the tie-breaker well to move ahead.
"I really don't know what went wrong," the 24-year-old Goffin said. "I was myself surprised by my high level of play in the first set, but then a bad service game at the start of the second set made it difficult for me.
"Probably it was my first match of the season and my legs were not ready. But I am sure I will play better on Friday. I just have to be consistent."
Goffin's quarter-final opponent will be Austrian Andreas Haider-Maurer, who came from behind to oust Jiri Vesely of the Czech Republic 6-7 (3/7), 6-4, 6-4.
The tournament, a warm-up for the Australian Open in Melbourne from January 19, will earn the winner on Sunday $73,400 and 250 ranking points.