Aminul made a polished 72 off 95 balls to guide the national flag carriers to a commanding 238-7 in the stipulated 50 overs after they were put in.

Narayanganj in their chase, never looked like toppling the challenging Biman total and were bundled out for 135 in 44.2 overs.

Aminul's match-winning effort came a day after his hopes for a Test-recall was dashed. The former national captain and country's first Test centurion was not considered in the 20-man preliminary squad for the tour of Australia announced on Friday for his inconsistent form in domestic cricket this season. But his vital knock on a difficult Comilla wicket bore all marks of his invaluable experience and left Biman just a step away from retaining the national championship title.

The holders will take on the winners of the second semifinal between Comilla and Rajshahi at the MA Aziz Stadium in the final scheduled for June. The second semifinal will be held at Chittagong today.

Coming into bat at his customary position of number four, Aminul held the Biman innings together after opener Jahangir Alam and one-down Moniruzzaman, a new face in the Australia bound probables' list, had departed early.

Jahangir returned to the dressing room without troubling the scorers. Moniruzzaman, the leading run scorer of the domestic season, failed to celebrate his maiden call to the senior team as he was out for just six.

With Biman reduced to 30-2, Aminul joined young opener Rashedul Haq to add 53 runs for the third wicket before Rashedul departed for 38 off 61 ball. He struck five fours and a six.

Aminul was also involved in an enterprising 74-run stand for the fifth wicket with wicketkeeper Sajjad Kadir, who scored a fluent 54 off 62 balls that included three massive sixes and two fours.

Aminul's workmanlike innings featured only three hits across the rope but when he was eventually castled by SH Mona, Biman were firmly placed on 210 for five.

Mosaddek Hossain came in and made a brisk 20 off 15 balls. The leg-spinner also captured three wickets for 37 runs after his exploits with the bat.

Biman's right-arm seamer Aminul jr. laid to rest any hopes of a Narayanganj fight back by dismissing both openers including the prized scalp of Shahriar Hossain.

Shahriar, the discarded national opener, threw caution to the wind with a quickfire 32 off 30 balls before being clean bowled by Aminul.