At tea, Sri Lanka were 351 for four having scored 166 runs in the session, extending their lead to 190.

Sri Lanka now look set to bat throughout the majority of the final session, building up a huge lead before their declaration, probably late this evening although they may wait until the morning.

Bangladesh had grabbed three quick wickets early in the day but De Silva showed all his experience as he cashed in on a friendly bowling attack.

De Silva brought up his hundred, his first since the 106 he scored against England at Galle, with a trademark leg-side clip having faced just 136 balls, hitting 15 fours.

Having waved his bat to the dressing room in celebration, he then raised the tempo, scoring his next 50 off just 36 balls with seven more boundaries.

On 171 from 194 balls at the break, he looked set for a double century and within sight of his previous career best, the 267 he scored against New Zealand in 1990/1.

Captain Sanath Jayasuriya appeared pedestrian in comparison as he played himself in carefully after the fall of left-hander Kumar Sangakkara.

But he adjusted well to his unfamiliar position in the middle order, reaching his 22nd Test fifty shortly before the interval.

Sangakkara had been unfortunate to be run out on 75, missing out on his fifth Test century.

De Silva was push hard for a comfortable three but Sangakkara slowed having though the fielder had crossed the boundary. When fielder Al Sahariar threw in the ball he slipped, providing Alamgir Kabir with sufficient time to throw down the stumps after collecting the ball at the non-strikers end.

Sangakkara, who failed to pass fifty against England in Sri Lanka's last Test series, faced 110 balls for his 75, hitting 12 fours.

Experienced left-arm spinner Enamul Haque, 36, continues to bear the brunt of the workload, bowling 25 overs for 101 runs so far in the day.

By lunch, Sri Lanka were 184 for three, having overhauled Bangladesh's 161 first innings total and established a 33 run lead.

Sangakkara was 67 not out having completed his eighth Test fifty and De Silva, deciding not to retire after the England tour, despite intimating that he would so during that tour, was 66 not out. Both players struck 11 boundaries.

Debutante Talha Jubair, 16, broke through in the first over of the day, exploiting the early morning moisture, as he slipped an inswinger through Marvan Atapattu's gate. Atapattu had failed to add to his overnight score of 20.

Russel Arnold (25), who had started the day fortuitously when he edged just wide of the wicket-keeper in the opening over, added 15 runs to his overnight score before cutting a short ball from Monjural Islam straight into the hands of Hannan Sarker at gully.

In the fifth over of the day, Jubair claimed his second wicket, as Mahela Jaywardene was dismissed for a duck. His feet rooted to the crease, he was clean bowled by a well-pitched inswinger.

Jayawardene's departure left the hosts precariously placed on 54 for three against the friendliest bowling attack in Test cricket.

But just when the selectors may have been ruing their decision to pick a second string squad for the second Test, the fourth wicket pair asserted their authority.

Sangakkara, relieved of the wicket-keeping duties in this game, and De Silva played positively, the pair bringing up their 50 partnership in just 54 balls and 100 in 128 balls.

All the Bangladesh seamers were expensive, with Jubair the most successful with two for 64 from his nine overs.

However, experienced left-arm spinner Enamul Haque, 36, proved more economical, although rarely penetrative, bowling ten overs for 37 runs.

Bangladesh, forced to attack with the ball after being bowled out for 161, a below par total on a good looking batting surface, nearly broke through when Marvan Atapattu edged a catch just wide of third slip in the first over.

But, thereafter, Atapattu and Russel Arnold, who retains his openers berth after his century at Old Trafford against England, took control, finishing the day on 32 without loss.

Atapattu punched four boundaries in his unbeaten 20 and Arnold's 10 not out included one emphatic pull and a crisp back foot drive.