Bangladesh fell short of completing a clean sweep over Zimbabwe in the five-match Twenty20 International series, losing the last game by eight wickets in Mirpur yesterday, however, clinched the series by a dominant 4-1 margin.

But the series was not as one-sided as the 4-1 margin would suggest with the Tigers' batting frailties getting exposed multiple times against an average bowling attack which resulted in a couple of close contests in the third and fourth T20Is, where the hosts won owing the visitors' own batting woes.

The nine and five-run victories in the third and fourth match respectively followed by the comprehensive defeat in the final game are raising concerns over the team's preparedness for the challenges that wait for them in the forthcoming ICC T20 World Cup.

However, skipper Najmul Hossain Shanto claimed that they have successfully crossed out the things they wanted to check in the series and said that winning the close contests have raised the team's confidence.

"We were serious in all the games. We didn't want to lose a game neither do we feel we needed to lose [to get a reality check]. I think we had a very good series," Shanto said at the press conference yesterday after the game.

"We had a few close games and in those scenarios, we practiced how the bowlers would execute their plans and how we can remain calm. You could say that in those close matches the game was in their hands and we were able to comeback. The way we did that is a positive sign which will work well for us in the tournament," he added.

There were some encouraging signs in the batting department, with opener Tanzid Tamim looking confident with his approach while Towhid Hridoy remaining fluid throughout the series.

Jaker Ali Anik put finishing touches to a few innings and Mahmudullah Riyad turned up too at times, like he did with a 54 in the fifth T20I.

The bowlers performed up to expectations barring the final game with an inspired Taskin Ahmed picking up the player-of-the-series award while leg-spinner Rishad Hossain also staked his claims for a place in the World Cup side.

There were a few lose ends with Mohammad Saifuddin and Tanzim Sakib's death-over displays but Mustafizur Rahman and Shakib Al Hasan's bowling since their return showed that the bowling group has depth.

Yet, the way the batting line-up crumbled in the fourth T20I after a 101-run opening stand between Tanzid and Soumya Sarkar is a worrying sign.

Shanto, however, felt the wickets used in the series played a role in the batting woes.

"The wickets were not batting friendly throughout the series. The batters tried to play well and assessed the wickets while batting," said the skipper.

Shakib and Shanto's batting form will be added concern alongside Liton Das's exploits this series, who was dropped from the final two T20Is.

Given that the World Cup is just a few weeks away, Najmul and Co have their work cut out as they have very little time to work on the shortcomings exposed in this series.