Del Potro wins Sydney InternationalJuan Martin del Potro of Argentina hits a backhand to Bernard Tomic of Australia during the final of the Sydney International tennis tournament in Sydney, Australia, Saturday, Jan. 11, 2014. (AP Photo/Daniel Munoz)
MELBOURNE, Australia (AP) -- Top-seeded Juan Martin del Potro outclassed defending champion Bernard Tomic 6-3, 6-1 Saturday in a 53-minute final of the Sydney International.
Del Potro finished the match with his eighth ace and made only four unforced errors in securing his 18th career title and first in Sydney. He lost only six points on his serve, and Tomic appeared dispirited after being broken to fall behind 4-1 in the second set.
''My forehand worked perfect, I made a lot of winners, many aces, played good slices,'' del Potro said. ''Every long rally we played, I won all of them, which is good for my confidence. I think Bernard was a little frustrated to see me very focused on the match and hitting the ball so well.''
Tomic was more succinct.
''I got killed,'' the 21-year-old Australian said. ''There was nothing I could do.''
It's about to get more difficult for Tomic. His next match is against top-seeded Rafael Nadal in the first round of the Australian Open. Del Potro will also play his first-round match Tuesday - against a qualifier.
In Auckland, New Zealand, John Isner had 23 aces in a match which had no service breaks to beat Lu Yen-hsun of Taiwan 7-6 (4), 7-6 (7) in the final of the Heineken Open.
Isner, ranked No. 14, won his eighth career singles title and took the title in New Zealand for the second time after his victory in 2010.
The third-seeded Isner, playing with a right ankle injury he picked up at the Hopman Cup the previous week, took a crucial minibreak to open the first set tiebreaker. In the second tiebreaker, he rallied from 3-0 down and closed with an ace on his third championship point.
''This match was very tight as every match I've played this week was very tight,'' Isner said. ''I needed every bit of it to come out on top.''
In the final of the Kooyong Classic exhibition event, Japan's Kei Nishikori joined his coach Michael Chang as a tournament champion with a 6-4, 7-5 win over Tomas Berdych.
Nishikori, seeded No. 16 at the Australian Open, was watched in the stands by Chang, a former French Open champion and a three-time winner at the Melbourne venue in 1995-97.
In the WTA event at Hobart, Spanish qualifier Garbine Muguruza defeated Klara Zakapalova of the Czech Republic 6-4, 6-0 to claim her first singles title.
The 20-year-old Muguzura, who did not drop a set from the qualifiers to the final, joins 2012 champion Mona Barthel as the only qualifiers to win the Hobart event.
Muguruza, ranked 58th, beat second-seeded and Wimbledon semifinalist Kirsten Flipkens in the quarterfinals, while Zakapalova defeated top-seeded and former U.S. Open champion Sam Stosur in the semis.
The 20-year-old Muguruza didn't play after Wimbledon last year because of right ankle surgery, and the recovery took longer than expected.
''I started to play on a chair, and then it was a little bit more until I was like normal,'' she said. ''I didn't expect to win a lot of matches in the second tournament of the year but I just know that I'd worked so hard before. I was like a big bull.''