NEW YORK, NY, USA - Together they led a Serbian revolution on the WTA, both getting to No.1 and playing deep in the Grand Slams time and time again - it has been an up-and-down last few years but Ana Ivanovic and Jelena Jankovic seem to be rising up again, and they both won on Thursday.

The No.12-seeded Ivanovic was the first of the pair to advance, having few problems in dispatching Sofia Arvidsson on Arthur Ashe Stadium, 63 62.

"I'm very happy about today's match because Sofia's a tough opponent. She retrieves a lot of balls and likes to use pace from her opponent," Ivanovic said. "I really tried to use the whole court and open up the court, and go behind her. I looked for my forehand and tried to be more aggressive on that side."

Ivanovic hasn't reached a quarterfinal in the last 17 Grand Slams - not since winning her first Grand Slam title at the French Open in 2008. But she has lofty ambitions, and is within striking distance of the world's Top 10 again.

"I want to get back to the top and get back in contention to win Grand Slams again," Ivanovic said. "It's been a long process of getting my mind there and my body and game and everything together. It's still going to be a lot of work.

"I'm really motivated."

Jankovic, the No.30 seed this fortnight, followed with a grinding 64 62 win over Spanish qualifier Lara Arruabarrena-Vecino on the outside courts.

"She was a tough opponent with a very Spanish game - a great forehand with a lot of spin, and very solid off the ground," Jankovic said. "I had to work hard for each point and stay solid and I'm happy I managed to win through today.

"Afterwards I went to the practice courts. I wanted to clean up some things. I played pretty well today, but I needed to do some things better. Anyway it was a good day at the office and I'm looking forward to the next round now."

Jankovic went into last week's warm-up event in Dallas having lost seven of her last eight matches and bottoming out at No.34 on the rankings; but she made it all the way to the final there, moved back to No.27 this week, and now with her two wins so far here has prevailed in six of her last seven matches.

"I struggled a lot this year but I've been working hard to improve my game - I've worked so hard and hopefully now it's starting to pay off," Jankovic said. "I was losing a lot of matches for a while. You start to get down. I'm not used to that - I was in the Top 10 for so long, I was No.1, I was used to being at the top. Two weeks ago I dropped to No.34 and now I'm back to No.27, so I'm on a roll again!

"I hope this is just the beginning."