NEW HAVEN, Conn. (AP) -- Anna Chakvetadze upset Jelena Jankovic on Monday in the Pilot Pen tournament that's missing most top players, who are preparing for the U.S. Open next week.
The unseeded Chakvetadze won 6-3, 3-6, 6-2 over the 10th-seeded Jankovic, who lost her first-round match for the second consecutive week since she began working with a coach.
"I don't have confidence so I'm not playing my best,'' said Jankovic, ranked 18th in the world. "I have a new coach now and he's changing little things in my game. So all the shots feel so insecure at the moment.''
Jankovic had reached the third round of each of her four previous tournaments before taking on Roman Savochkin as coach. Since then, she's worked to improve her serve and fitness, but her legs felt heavy Monday after intensified workouts in recent weeks.
Before working with Savochkin, she didn't have a formal coach on the tour. Now she's not sure if she'll stick with him.
"I don't know,'' she said. "I will see because now I'm not playing so good.''
Jankovic led the third set 2-1, then lost the remaining five games. She dropped the fourth game without getting a point, and the long fifth game reached deuce seven times before Chakvetadze broke her serve.
Jankovic then managed just three points in the last three games and was hurt by three double faults on her last 13 service points.
For the first time in the Pilot Pen's eight years, it also is holding an ATP event for men with total prize money of $585,000. Three of the world's top 20 ranked players are entered, led by No. 6 Nikolay Davydenko.
There also was an upset Monday on the men's side when 18-year-old Scoville Jenkins of Atlanta, ranked 372nd in the world, won his first ATP match in three tries. He beat Jarkko Nieminen, ranked 55th, 2-6, 6-3, 6-4.
"I was pretty nervous in the first set,'' said Jenkins, whose first ATP match was against Andy Roddick in last year's U.S. Open. "I was excited (to win) but I know that this is only the first round.''
His next opponent is fourth-seeded Tommy Robredo.
On the women's side, with total prize money of $600,000, the top two seeded players are Lindsay Davenport, who slipped to second in the world rankings Monday behind Maria Sharapova, and Amelie Mauresmo, ranked third.
Mauresmo took five weeks off from the tour -- not even picking up a racket for the first two -- then practiced for three weeks before reaching the semifinals in Toronto, where she lost last Friday.
She has a first-round bye and is eager to sharpen her game for the U.S. Open, where she reached the quarterfinals last year. She customarily takes a rest before that tournament.
"I want to play the different matches and put my rhythm a little bit more into place on the court. I'm playing good,'' Mauresmo said. The time off "makes you maybe a little more fresh and competitive and relaxed so that's the case every time I go there.''