Sehwag's unbeaten 128 came in 122 balls

India's Virender Sehwag hit an unbeaten century, but four late quick wickets gave Sri Lanka a slight edge in the rain-hit first day of the second Test.

Having chosen to bat, India looked set for a commanding total with Sehwag (128 not out) and Gautam Gambhir (56) putting on a 167-run opening stand.

But after a rain break Ajantha Mendis (2-74) and Chaminda Vaas (2-57) struck to reduce India to 214-4 in Galle.

India trail in the three-match series after a heavy defeat in the first Test.

And the visitors started as if they were intent on undoing the wrongs of their innings and 239-run defeat in Colombo.

Sehwag and Gambhir raced to 151-0 at lunch off just 29 overs, with Gambhir, then on 13, offering the only chance of the session when he was dropped by Kumar Sangakkara at first slip.

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Sehwag reached his 15th Test century with a glorious six over long-on off Vaas, but Mendis broke the opening partnership by trapping Gambhir lbw.

Gambhir, whose half-century came in 92 deliveries, challenged the dismissal but he was unsuccessful and more wickets soon followed to leave India reeling on 178-4.

Rahul Dravid (2) was caught at silly mid-on by Malinda Warnapura off Mendis, while Vaas claimed the prized wicket of Sachin Tendulkar (5) lbw and then, in the same over, had Sourav Ganguly caught behind for a duck.

VVS Laxman survived an lbw decision as he and Sehwag consolidated the innings with a 36-run partnership before bad light prematurely ended play.