Maria Sharapova has praised Alexandra Dulgheru after being forced to fight back from a set behind to beat the Romanian at the US Open.

The number five seed, who edged out her opponent 4-6 6-3 6-2 in New York in the early hours of this morning, is feeling positive heading into round three of the showpiece event.

"She played really well," Sharapova is quoted as saying by The Independent. "Although I started off really well in the first couple of games, I didn't take the opportunity to go up 3-0. After that she started getting a little bit of a rhythm.

"It was difficult. Obviously the conditions were tough. You start in the sun, you finish under the lights. It was a very long match. Overall I felt like in the end I was in much better shape than she was and I could have played another few sets. Mentally that helped me a lot.

"I think physically I'm in a very good position. I think that's shown a lot in my three-set statistics this year. I think I played more at this point in the year than I have in all of my career. The numbers are quite high, and I've been able to recover quite well."

Sharapova will face Sabine Lisicki in the next round.