Former world number one Ana Ivanovic made a strong start at the U.S. Open on Tuesday but said she was playing with a heavy heart after hearing about the drowning death of a childhood friend back home in Serbia.
Vukasin Ziramov, 25, died last week after jumping off a bridge into a river while on an outing with friends in Senta.
"It's been very sad news," Ivanovic, the 13th seed at Flushing Meadows, told reporters after her 6-2 6-0 rout of Anna Tatishvili of Georgia.
"It was very hard because it was almost like my relative. We grew up, and I knew him since we were kids. It's very, very sad."
It was very hard because it was almost like my relative. We grew up, and I knew him since we were kids. It's very, very
On the court, Ivanovic showed the positive effects of working with a new Serbian conditioning and coaching team she took on after Wimbledon as she works her way back after a disappointing stretch in her career.
The 25-year-old Serb, who rose to the top ranking in women's tennis in 2008 after winning the French Open, had dropped to 22 in the rankings in 2011.
Ivanovic ranked 15th heading to Flushing Meadows.
"I was playing really well and I had a few tough losses," Ivanovic said about a hardcourt build-up that included a three-set loss to Victoria Azarenka in Carlsbad, a third-set tiebreaker loss to China's Li Na in Toronto and a three-set loss France's Alize Cornet in Cincinnati.
"I'm very confident with the game and the way I was playing," she said, adding she was concentrating on conditioning and making her serve and forehand more dominant.
Ivanovic said she was driven to return to the upper echelon of the game.
"It's my only goal I have at the moment," she said.
"I really want to get back to the top of the game. I believe I have qualities to do so.
"Once you're in the top, you don't really feel satisfied with being in the top 15. You really want to aim and push yourself. That's where I am at. I really want to put my head down and work hard and try to maximise my potential."
Five-time U.S. Open champion Roger Federer gave evidence he could still be a force with a commanding 6-3 6-2 7-5 victory over Grega Zemlja of Slovenia in his opening match.
The Swiss master, who suffered a shock second-round loss at Wimbledon in June and entered the U.S. Open as the seventh seed, dominated the 62nd ranked Zemlja, ripping 35 winners and committing just 16 unforced errors in the 93-minute win.
The match had been scheduled to cap the Monday night program at Arthur Ashe Stadium but was postponed because of rain. The 32-year-old Federer, winner of a record 17 grand slam singles titles, will next play Carlos Berlocq of Argentina, a 6-3 3-6 6-7 (6) 6-4 6-2 winner over Colombia's Santiago Giraldo.
Giraldo had led Berlocq 2-1 in the fourth set when Monday's rain forced them to complete their match on Tuesday.
In the women's draw, sixth seed Caroline Wozniacki and seventh seed Petra Kvitova are also through to next stage.