Sania Mirza [Images] romped into the second round of the US Open with a straight-set win over Croatia's Karolina Sprem on Tuesday.

The Indian ace, who dropped out of the top-50 on the WTA rankings released on Monday, beat Sprem 6-4, 6-2 in the first round. Sania will next play the number 14 seed Francesca Schiavone of Italy [Images], who was a 6-1, 6-2 winner over Oprandi Romina.

Sania, who lost in the quarter-finals at the Forest Hills US Open primer last week, was steadier on her serve and more aggressive with her groundstrokes.

She got the breakthrough she was looking for in the 10th game to take the opening set 6-4.

She pushed home the advantage, jumping out into a 4-1 lead and taking the set 6-2 to move into the second round.

"I stuck to my game plan. She was a tough player to get in the first round. She has been in the top 15 in the world, said the Indian, who reached the fourth round of the US Open last year.

"My serving was the key. Hardcourt is my favourite surface. It's faster than at the Australian and the French and New York is my favourite place."    

Andy Roddick [Images] served notice that he is primed for a run at another US Open title by whipping Florent Serra in straight sets on Monday to lead a parade of seeded players into the second round of the year's final Grand Slam.

"I'm really, really confident right now," said the ninth seeded Roddick after his dominating 6-2, 6-1, 6-3 triumph in the opening session.

There were few upsets at the National Tennis Centre, with the notable exception of third-seeded Ivan Ljubicic, who was ousted by Spain's Feliciano Lopez, 6-3, 6-3, 6-3.

On the women's side, advancing to the second round were number two seed Justine Henin-Hardenne, number four seed Elena Dementieva and 10th seeded Lindsay Davenport [Images].

Under the watchful eye of new coach Jimmy Connors, Roddick needed just 75 minutes to bounce Serra from the tournament. The former world number one now faces Kristian Pless of Denmark or Alberto Martin of Spain in the second round.

"It felt clean," said Roddick, the 2003 Open champion who was shocked by Luxembourg's Gilles Muller in the first round last year.

LARGE STEP

"I hit them well today. A little short the first couple of games but I think I broke him more than he held serve today and that's a large step for me.

"I'm putting a lot of returns in the court and I'm doing something with them."

The 23-year-old Roddick, who rebounded from an inconsistent summer by winning the Masters Series event in Cincinnati this month, kept Serra off-balance by firing 10 aces while getting 70 percent of his first serves in.

Roddick said he enjoys the "presence" of the 53-year-old Connors, a five-times US Open champion and one of the greatest players to ever step on the court.

"I'm excited every morning when I wake up to try to learn new things," said Roddick. "His passion for the game and for this process is huge. It's contagious."

Henin-Hardenne overwhelmed Italy's Maria Elena Camerin 6-2, 6-1 in 74 minutes, just two days after she captured the New Haven title in her only post-Wimbledon tournament.

BEWILDERING PLAY

Injury-prone Henin-Hardenne blasted 24 winners past her bewildered opponent and looked in form despite sitting out much of the summer with a nagging knee injury.

"The transition from New Haven to here wasn't very easy because I didn't hit a single ball here on the US Open courts before my warm-up for my match today but I feel good," she said.

The 24-year-old Belgian, who won the 2006 French Open and was a finalist at the Australian Open and Wimbledon, is not making any predictions about her title chances.

"I'm not thinking too much about what could happen here," she said. "I'm healthy. That's very important. My knee is feeling fine. I just have to be careful."

Advancing along with Henin-Hardenne was Davenport, who showed no signs of the shoulder injury that forced her to retire from the New Haven final.

The 1998 champion needed just 52 minutes to stop Czech Klara Zakopalova 6-1, 6-4. Despite the easy victory, the former world number one was just settling in at Flushing Meadows.

"I'm not looking at the big picture of the whole New York experience yet," said Davenport. "Today was the first day I came here. You have to play.

"So I haven't really had time to digest exactly what's going to happen in the ensuing days or weeks."

Dementieva advanced with a 6-1, 6-4 victory over American Laura Granville, while number six seed and 2004 champion Svetlana Kuznetsova stumbled briefly but recovered to beat Germany's [Images] Sandra Kloesel 6-2, 2-6, 6-3.

• Complete tennis coverage
• All you want to know about Sania Mirza