CHENNAI, India (AP) -- Australian Open champion Stan Wawrinka advanced to the quarterfinals of the Chennai Open by beating Croatian teenager Borna Coric 6-1, 6-4 Wednesday.
The top-seeded Swiss, the defending champion in Chennai, won five straight games to open the match.
''Every year you have to start from zero, but I'm quite happy with today as I was feeling the ball well,'' said Wawrinka, who is preparing to defend his lone Grand Slam title later this month in Melbourne. ''I started really well and had some other chances for service breaks in the second.''
Wawrinka will next play eighth-seeded Gilles Muller of Luxembourg, who defeated Elias Ymer of Sweden 6-4, 6-3.
Also, fourth-seeded David Goffin of Belgium defeated Ricardas Berankis of Lithuania 6-0, 4-6, 7-6 (1).
''It was a tough one to start the season with,'' said Goffin, who had 12 aces. ''I played really well in the first set but it was tough to maintain my level. It's not always easy when you win the first set 6-0. It was really close after that because he served very well in the second set.''
Goffin will next face Andreas Haider-Maurer in the quarterfinals. The Austrian beat Jiri Vasely of the Czech Republic 6-7 (3), 6-4, 6-4.