KANPUR, Nov 23: Opener Virender Sehwag hit a sparkling century as India kept on course for a big score in the first Test against South Africa at the Green Park Stadium here on Tuesday.

The home side reached 401-4 at stumps on the fourth day after the big-hitting batsman slammed 164 and starred in an opening stand of 218 with Gautam Gambhir (96). Captain Saurav Ganguly (57) and Rahul Dravid (52 not out) built on the fine start as India posted a fitting reply to South Africa's first innings total of 510-9 declared.

Sehwag and Gambhir achieved only the sixth opening stand of 200 or more for India and the second-best ever for their country. The Delhi pair, 85 apiece overnight, began briskly after a delayed start due to fog, but slowed down as Gambhir approached what could have been his first Test century in only his second match.

"It was disappointing not to get a hundred as the first Test century is always important for any batsman," said the left-hander. "I did get nervous close to the three-figure mark."

They still managed a healthy run-rate on the flat batting track, using up only 52.3 overs. The stand was broken when Gambhir was caught behind by debutant wicket-keeper Thami Tsolekile to give Shaun Pollock his 350th Test scalp.

Sehwag's eighth Test century in 28 matches was studded with 20 boundaries and a six each off left-arm spinner Robin Peterson and paceman Andrew Hall to thrill the crowd of around 30,000.

He shifted gears after lunch, scoring his last 56 runs off just 35 balls to move from 108 to 164. The attacking batsman created space to unleash some fine shots on either side of the wicket during his 228-ball knock.

"We had a very good understanding in the middle as we managed to rotate the strike," said Sehwag. "Having played together for Delhi helped a lot as we kept taking singles with confidence."

Sehwag was eventually trapped lbw by Hall, who also removed Sachin Tendulkar (three) with a ball that came in sharply and hit the wicket off his pads. Gambhir struck 11 fours and a six off 151 deliveries.

Ganguly hit seven boundaries during his half-century and added 96 runs for the fourth wicket with Dravid, who hit five fours in a cautious knock of 169 balls. Ganguly was caught at long-leg by Peterson off medium-pacer Zander de Bruyn when he went for a big hook shot. India's highest first-wicket stand, a world record, was 413 by Pankaj Roy and Vinoo Mankad against New Zealand in Chennai in 1955-56.

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