Skipper Angelo Mathews held his nerve under pressure and led from the front with an unbeaten half-century as Sri Lanka registered a three-wicket win over Bangladesh in the concluding league fixture of the Asia Cup here today.

Sri Lanka chased down the 205-run target with an over to spare, thereby maintaining their unbeaten streak in the tournament, after Bangladesh opted to bat in the inconsequential match at the Shere Bangla National Stadium.

Having already made the final alongside Pakistan, Sri Lanka were in big trouble at eight for three in the third over, before being reduced to 75 for five at the midway stage by a spirited Bangladesh attack.

But Mathews (74) did not panic as he struck seven boundaries and one six en route to his 19th ODI half century, finishing the chase by pulling Arafat Sunny for a boundary.

The skipper found a perfect ally in Chaturanga de Silva (44 from 52 balls; 5x4) and the duo stitched 82 brisk runs for the sixth wicket.

With four wins from as many matches, the Lankans finished atop the table with 17 points, while Pakistan finished with 13 points. India (9) and Afghanistan (4) ended at third and fourth places, while hosts Bangladesh finished with the wooden spoon with four defeats.

The summit clash will be held here on Saturday.

Earlier, Bangladesh frittered away a solid start by their openers to be restricted to 204/9 after Mushfiqur Rahim opted to bat on an uneven looking slow surface.

Rookie Priyanjan, with his off-spin, grabbed 2/11 from three overs after Mendis gave the breakthrough with two wickets from one over. Bangladesh's opening duo had put on 74 runs.

Opener Anamul Haque, who scored a century in their record 326 against Pakistan, struck one six and two fours en route to an 86-ball 49.

In the next over, Priyanjan took the prized scalp of Shakib-al-Hasan (20), while the pace duo of Suranga Lakmal (2/32) and Thisara Perera (2/29) tightened the noose in the death overs.

In their defence, Bangladesh came out all guns blazing as Al-Amin Hossain dismissed Kusal Perera for a duck in the second ball of Lankan innings, before grabbing the prized scalp of Kumar Sangakkara (2) in his next over. 

With nothing going their way, Sri Lanka lost a third wicket when Mahela Jayawardene was run out for a duck after a confusion with Thirimanne, giving the hosts a real possibility of causing an upset.

Sri Lanka had two small partnerships with opener Thirimanne (33) and Priyanjan (24) in the middle before pacer Ziaur Rahman bowled an absolute beauty to dismiss the latter.

Ziaur generated enough bounce from a good length and it was simply unplayable for Priyanjan, while Thirimanne's patient innings was halted with Rubel Hossain taking a spectacular running catch at the straight boundary.

The blinder brought alive the Bangladesh camp.

But Mathews showed the right temperament and rotated the strike cleverly with de Silva and the duo ensured that the required run-rate was taken care of.

Bangladesh suddenly looked disoriented on the field as they missed a catch of de Silva and a run out of Perera.

Earlier, Bangladesh had a solid start with Anamul and Shamsur Rahman looking comfortable against new ball bowlers Suranga Lakmal and Thisara Perera.

The duo scored mainly in boundaries before a dubious lbw decision by Bruce Oxenford gave Mendis the first breakthrough in Rahman.

There was a double blow for Bangladesh as Mendis took another in the same over when he castled Mominul Haque.

Bangladesh struggled for a partnership in the middle with de Silva trapping the in-form skipper Mushfiqur Rahim for 4, leaving Anamul stranded at the other end.

In pursuit of their first win in the ongoing event, the hosts made three changes to the XI for the last league game.

Bangladesh omitted Shafiul Islam, Abdur Razzak and Kayes for Rubel Hossain, Arafat Sunny and Rahman.

Opener Kayes, who made a fifty in the last match, was unavailable due to injury.

Sri Lanka rested Lasith Malinga and brought in Senanayake while Dinesh Chandimal gave way to Priyanjan.

The match has been rendered inconsequential as Sri Lanka and Pakistan have already made the final.