Top seed Karan Rastogi felt the heat, quite literally, against an unrelenting Aditya Madkekar before securing a hard-fought 6-4, 2-6, 6-1 win to enter the quarter-finals of the ITF Futures Men's Tennis Tournament in Delhi on Wednesday.

Meanwhile, Karan's new-found nemesis and fifth seed Prakash Amritraj continued his fine form, outplaying qualifier Gursharan Singh 6-3, 6-1 to set up a quarter-final clash against Chinese Taipei's Hsin-Han Lee, who defeated Ashutosh Singh 6-3, 7-6 (4).

In the marathon match lasting more than two-and-a-half hours, Karan had his back against the wall most of the time in the first two sets and just about managed to come through as Aditya seemed to have given up towards the end.

The top seed played out a rather scrappy game with his serve being the weakest link. He was broken in the very first game and was trailing 1-2 before managing to break back -- courtesy an unforced error committed by his opponent.

Aditya had his share of chances but failed to convert them much to the relief of Karan, who got another lucky break in the eighth game, when Aditya hit a forehand long.

Karan was broken again in the ninth game, but leading 5-4, he took the opener after Aditya committed another unforced error.

Having lost the first set rather closely, Aditya came back strongly in the second set breaking Karan thrice in a row. Serving for the set, Aditya drew level with a well-executed lob, leaving Karan to fling his racket in disgust.

With some close line calls going his way, it was Karan's turn to stage a comeback in the decider and the Davis Cupper held serve besides breaking Aditya twice to seal the issue.

Karan will take on eighth seed Navdeep Singh in the quarter-finals. Navdeep beat wildcard Tushar Liberhan 6-0, 6-2 in his second-round match.

"I wasn't really playing well but somehow managed to pull through as I had the confidence. The heat was a bit unbearable but you can't really complain as it is same for both of us," a relieved Karan said after the match.

For Aditya it was dejection after coming so close to scoring an upset win.

"Sometimes playing well is not enough. You have to have the luck going your way which was not the case with me today," Aditya said.

In another exciting second-round match, Sanam Singh upset Britain's Robert Searle 6-3, 6-4. The 19-year-old Chandigarh-lad was swift on the baseline and his fierce forehand returns forced Robert to commit errors.

A frustrated Robert, who is ranked over 100 places above the Indian in rankings, was left swearing at his racket as Sanam emerged on top after dominating the match.

He will now be up against fourth seed Sunil Kumar Sipaeya, who beat qualifier Rohan Gujjar 6-1, 6-4.

In the other second-round matches, Vishnu Vardhan upset Britain's Matthew Smith 6-4, 6-1 to enter the last-eight stage, where he will take on Vinod Sridhar.

Vinod won against Chinese Taipei's Tsung-Hua Yang 6-2, 6-4 in his second round match.

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