Charith Asalanka starred and Bhanuka Rajapaksa celebrated his birthday with a half-century as Sri Lanka beat Bangladesh by five wickets in the T20 World Cup.

Mohammad Naim (62 off 52 balls) and Mushfiqur Rahim (57 not out from 37) got the Tigers up to 171-4 after they were put in the battle of the qualifiers at Sharjah Cricket Stadium on Sunday.

Sri Lanka were in trouble on 79-4 when Wanindu Hasaranga fell after Shakib Al Hasan (2-17) dismissed Pathum Nissanka and Avishka Fernando in the ninth over.

Asalanka and Rajapaksa came to the rescue with a fifth-wicket stand of 86, setting up a victory in their opening Super 12 game that was sealed with seven balls to spare.

Opener Asalanka returned to form with a brilliant unbeaten 80 from 49 balls, while Rajapaksa benefited from two gifts from Liton Das on his 30th birthday.

The left-hander from Colombo was dropped twice by Das and capitalised on those let-offs by scoring 53 off 31 balls before departing in the penultimate over.

Sri Lanka's highest successful run chase moved them level on points with leaders England and Australia in Group 1, also halting a run of three consecutive T20 defeats against the Tigers.

TIgers batsmen Naim and Mushfiqur show their teeth

Naim and Mushfiqur played superbly to get the Tigers up to a good total after they were 56-2 in the eighth over when the dangerous Shakib departed, having been cleaned up by Chamika Karunaratne (1-12) for only 10.

Opener Naim brought up his fourth T20I half-century – and a second of the tournament – off 44 balls, finding the rope six times before he was caught and bowled by Binura Fernando. Mushfiqur struck two sixes in an enterprising, classy knock as he brought out his full repertoire of strokes.

Asalanka steps up, Rajapaksa grateful for Das gifts

Sri Lanka had been going along well on 54-1 at the end of the powerplay, but there was work to do when the Rajapaksa joined Asalanka at the crease.

Das spilled the birthday boy in the deep when he was on 14 and then 23 as Bangladesh felt the heat. Asalanka never looked troubled in his maiden T20I half-century, hitting five sixes and as many fours, with Rajapaksa clearing the rope three times in an impressive run chase.