Javed Omar made just six off 24 balls on Tuesday
The two teams play the second in the three-match series in a day-night encounter in Dhaka on Thursday.
In Saturday's 49-run defeat in the first one-day international in Chittagong, the home side slumped to 68 for six.
That was before Mashud, 54 not out, gave their score some respectability with Enamul Haque, 32, lending support.
Application
And Mashud was in no doubt where his team needed to concentrate its improvement after their bowlers managed to restrict Pakistan to 202 all out.
He said: "We cannot do well unless our top-order applies itself better.
"We should learn to value our wickets and not play unnecessary shots."
Bangladesh, thrashed by an innings in each of the two Test matches on the tour, have much to play for in the back-to-back matches under lights on Thursday and Friday.
Spectators in the capital are anxious to see their team win something against another Test-playing nation.
Mashud was happy with his team's bowling effort, but rued the lack of application by the batsmen.
"I hope we don't repeat mistakes. We could have won if the top five batsmen had got runs, but they came under pressure," he said.
The wicketkeeper did, however, praise young seamers Mohammad Sharif, 17, and Tareq Aziz, 18, who claimed three wickets each.
Example
"Our fast bowlers give us a lot of hope for the future," said Mashud.
Bangladesh's Australian coach Trevor Chappell also praised the medium-pacers, but was less complimentary about his batsmen.
He said: "It was nice to see the lower order batsmen put their heads down and bat for a while. It was a good example for the others who are known as batsmen."
Pakistani captain Waqar Younis conceded his team had been given a fright at Chittagong.
"The thought of defeat came to my mind when we started badly," said Waqar. "But Rashid (Latif) played well and helped us get a handy total."
Latif hit a career-best 78, ensuring Pakistan won and burying memories of the 62-run loss to Bangladesh in the 1999 World Cup in England.