Another opener Mizanur Rahman gave Zakir an ably support as the duo shared a 166-run for the opening stand to set the platform of a famous victory.
Before being bowled out by pacer Kamrul Islam Rabbi, Mizanur clubbed 93 off just 82.
While Mizanur missed out a deserved ton by seven runs, Zakir serenely picked up his ton off 107 balls. He was also removed by Kamrul Rabbi after hitting 117 off 116, smacking 13 fours and one six. Rupganj's Indian recruit Baba Aparajit was the other batsman to fall for 11.
However, utilising the platform set by Zakir and Mizanur, Marshall Ayub (23) and Fazle Rabbi (10) sailed the side home with ease.
Apart from Kamrul Rabbi's two-wicket haul, Tanzim Hasan Sakib took the rest of the fallen wicket.
Abahani found them in a vulnerable state at the outset, being reduced to 48-4 but Naim Sheikh came as the rescuer for the team. He played patiently to help Abahani recover from the shaky start.
All-rounder Saifuddin was the other notable scorer with 40 not out and skipper Mosaddek Hossain Saikat made 37.
Naim who came to open the innings, finally got his fifth List A century. His century came off 113 balls and before being out, he scored 115 off 132.
Fast bowler Mukidul Islam Mugdho was the most successful bowler for Rupganj, taking three wickets while Shorifullah and Farhad Reza bagged two wickets apiece.