Virender Sehwag blasted his first half century in nearly 10 months and put on an unbeaten century stand with Gautam Gambhir as India made a blazing start on the opening morning of the first Test against England here today.

Sehwag was batting on 79 off only 66 balls, laced with 12 fours and a six while Gambhir remained unconquered on 37 in 103 balls as India went for lunch at 120 for no loss after skipper Mahendra Singh Dhoni opted to bat first at the Sardar Patel Stadium.

The Delhi duo, who had failed to fire in unison for some time, stitched their 11th century stand for the opening wicket and their first in nearly two years. The last century stand between them was the 137 at Centurion Park in second innings of the opening Test against South Africa in December, 2010.

Sehwag and Gambhir started a tad shakily with the latter inside-edging James Anderson close to his stumps for the first of his three boundaries and the former being almost bowled by Stuart Broad while attempting an expansive drive and missing the ball.

However, after Sehwag whipped a ball from Anderson off his hips for his first four in the fifth over, things settled down for the Delhi duo on a bone-dry wicket of a slow pace pitch where the ball hardly rose above shin level unless banged short.

Sehwag packed off Anderson from the attack by smacking him for three fours between third man and covers in the bowler's fourth over while Gambhir struck his second four by turning Broad off his legs. Anderson's opening spell was a costly 4-0-24-0.

The duo's aggressive batting helped India race to 50 in the 12th over and at the end of the first hour, the hosts were 61 without loss, prompting England to summon off-spinner Graeme Swann in place of Broad immediately after the first drinks break. Broad gave away 23 runs in his six-over spell.

Sehwag hit the accurate Tim Bresnan for a couple of boundaries in the off side when the bowler erred in line. The Najafgarh marauder pushed Swann for a single to the off to complete his 50 in 45 balls and 81 minutes.

It was the batsman's 33rd half ton in his 99th Test and the second after his second innings 62 against Australia in the fourth and final Test at Adelaide in January.

Growing in confidence, Sehwag blasted Bresnan for two four and a six over long on in successive balls to further stamp his authority on the proceedings.

Fifteen runs came off the 19th over of the innings as the home team's as well as the partnership's hundred came in the first ball of the next over in 89 minutes. It was the duo's first three-figure stand after 26 innings.

Bresnan, after his expensive sixth over, was replaced by Broad at the far end of the ground to bowl the 21st over. The pace bowler operated without a slip fielder against Sehwag just before lunch.

Just before the break, the visitors brought on left-arm spinner Samit Patel in place of Broad after the latter's 2-over second spell for seven runs and the bowler's first ball, a full toss, was hit for a boundary by Sehwag.

In the morning, India left out Harbhajan Singh, Ishant Sharma, Murali Vijay, Ashok Dinda and Ajinkya Rahane. England omitted Steven Finn, Joe Root, Jonny Bairstow, Graham Onions, Eoin Morgan, Monty Panesar and Stuart Meaker, giving opener Nick Compton his first Test cap.