Karan Rastogi [Images] halted Sanam Singh's winning streak with a 7-5, 6-3 victory and advanced to the men's singles semifinals of the State Bank of [Get Quote] Saurashtra National Grass Court tennis championships in New Delhi [Images] on Thursday.

Seventeen-year old Sanam, a wild card entrant, fought his way back after being broken early in either sets before going down to the second seeded Rastogi at the DSOI Courts.

Top seed Rohan Bopanna was in erratic form as he needed an hour and 34 minutes to overcome Divij Sharan 7-6 (4), 6-4.

The Davis Cupper fired 19 aces but also made 10 double faults. Twice, he made three of them in the same game to drop serve.

Bopanna will face Vishnu Vardhan in the semi-final. Vardhan advanced into the last four after Ashutosh Singh retired with a back spasm.  He was leading 7-5, 4-3 when Singh threw in his towel.

Rastogi's opponent will be Vishal Uppal who put paid to the hopes of Yasser Arafat Mohammad 6-2, 6-3.

After going down 3-0, Sanam bounced back to level it 3-3 in the first set.

Serving to stay in the set, the Chandigarh boy committed a double fault to go 30-40 but delivered an ace to deuce in the 10th game.

He saved one more set point before holding serve but was not so lucky next time.

Another double fault saw him face a double breakpoint. Rastogi then slammed a weak second serve deep into Sanam's right side court which the latter hit long to concede the set.

Rastogi at the other end turned on the heat. He had a double breakpoint opportunity in the fourth game, and after missing out on the first, converted the second with a return winner.

But Sanam refused to go down without a fight, saving three match points and forcing as many breakpoints as Rastogi tried to serve out the match in the ninth game.

Sanam was extremely unfortunate as a Rastogi serve on breakpoint skidded along the ground.

The latter eventually prevailed when Sanam put a backhand retrieve into the net.

Women's top two seeds, Rushmi Chakravarthy and Isha Lakhani, had to work hard for their semifinal berths.

Rushmi was stretched by Sandhya Nagraj who made a stunning comeback in the second set before the former pulled away in the decider to win 6-3, 3-6, 6-1.

Isha won the battle of Mumbaikars with a 6-3, 7-5 vicory over Sonal Phadke.

Isha will take on in the semifinals Sanaa Bhambri, the third seed who sailed to a 6-1, 6-0 win against Parul Goswami.

In the other quarterfinals, Punam Reddy ousted Archana Venkataraman 6-2, 6-1.

Isha capitalised on Sonal's double fault to break serve in the fourth game and held on to the advantage to take the first set.

The energetic left hander then went up 2-1 in the second set and saved five breakpoints in the sixth game.

She dropped serve in the 10th but broke back in the very next game before serving out the match after an hour and 40 minutes.

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