Montinee, who battled through the qualifying competition, trounced American wildcard Lauren Barnikow 6-1 6-2.

Her compatriot Suchanan was extended to three sets by Teodora Mircic of Serbia and Montenegro 4-6 6-2 6-4.

Montinee said she sustained a hamstring injury in the qualifying round and decided to just go for broke. "I felt stiff on my left hamstring and did not feel like running too much. I hit a lot of winners

and didn't give her momentum to play the way she would like to," she said.

Montinee is on the third week of the US tour and, unless she makes a quick recovery, the injury might affect her second-round match against qualifier Yasmin Schnack. The American rising star upset seventh-seed and former top 30 player Tatiana Panova, of Russia, 6-3 1-6 7-5.

"I feel uncomfortable while I serve. But a doctor gave me some medicine and put an ice pack on my hamstring. I hope I will be better before the match," said Montinee, who expected a tough challenge from an opponent she had never played before.

"I watched her play Panova. She played aggressive tennis. I wonder why her ranking is outside the top 1,000 - as I believe she is good enough for a top 300 place.

"I will have to be at my best against her. I have to open up the court with my backhand and go for my shots. I will also have to keep my percentage of first serves high," she said.

Suchanan will play Canadian Stephanie Dubois, who eased past American wildcard Maria Sanchez 6-2 6-1.