Bangladesh, led by their captain Mohammad Ashraful, may have extended the first Test against Sri Lanka to the fifth day in Mirpur, but the visitors are confident of wrapping up a win on Wednesday.

Boosted by Ashraful's half-century, Bangladesh closed the day at 254 for 5 chasing an improbable 521. Although the past month has seen India and South Africa pull off record chases, it's unlikely Bangladesh will be able to manage a further 267 runs; no team has chased 500 in a Test before.

Tillakaratne Dilshan, the Sri Lanka batsman, said his team were looking forward to a win. "They will be under pressure on the fifth day because they need to get around 270 runs and we need only two wickets to expose their tail," Dilshan said after the day's play. "Tomorrow [Wednesday] after two overs, the new ball will be available for us so we have a very good chance to win this Test match."

Bangladesh began their chase with a brisk opening stand of 40 between Imrul Kayes and Tamim Iqbal, who made 47. Tamim said the surface at the Shere Bangla National Stadium was the best he had encountered in a home Test. "It has even bounce and is not slow and low," he said. "It is a pitch that keeps both the batsmen and the bowlers interested."

Tamim felt if Bangladesh's overnight pair of Ashraful and Shakib Al Hasan - who added an unbroken 74 - hold out till lunch on the fifth day, the hosts had a shot at winning. Tamim, though, failed to convert a promising start, dismissed while going for a rash pull, which he admitted might have come about due to his anxiety. "I have been getting lots of 20s and 30s during the past few months and that played on my mind when I moved into the 40s. Maybe I was a bit nervous and wanted to get to the half-century quickly.

"I thought I could relax a bit once I reached that mark. It was a wrong shot to play at that stage and probably it was not one of my strengths. Maybe on another day, another situation and I would have thought differently."

Tamim said he was "more to blame" for the run-out of Kayes, and defended the team's attacking approach against Muttiah Muralitharan. "The best thing is to be positive against him as Ash [Mohammad Ashraful], who I think plays Murali the best, showed. I think the attacking intent from our batsmen was good but maybe we could have done without a few errors in judgment.

"I was more comfortable in the second innings against him and I am sure If I play him a bit more then I will be even more confident while facing him."