Earlier, Bangladesh have won the toss and opted to bat first.Zimbabwe handed Under-19 allrounder Wesley Madhevere an ODI debut.
Mortaza returned to the side after leading the team to eighth place in the World Cup in England last year.
Bangladesh are looking to show the same dominance that they have demonstrated in the one-off Test winning the match by an innings and 106 runs.
Before heading to this game, Bangladesh and Zimbabwe faced each other in 72 ODIs with Bangladesh winning 44 of them, and Zimbabwe winning 28.
It is only the second ODI at the Sylhet venue. The first and previous ODI was played in Sylhet back in 2018 between Bangladesh and West Indies.
While the series opener is taking place today, the remaining matches will be played on March 3 and 6 respectively. After the ODI series, both teams will lock horns in a two-match T20I series in Dhaka respectively on March 9 and 11.Bangladesh playing XI: Tamim Iqbal, Najmul Hossain Shanto, Liton Das, Mushfiqur Rahim (wk), Mohammad Mithun, Mahmudullah Riyad, Mehidy Hasan, Mohammad Saifuddin, Taijul Islam, Mashrafe Mortaza (capt), Mustafizur Rahman
Zimbabwe playing XI: Chamu Chibhabha (capt), Tinashe Kamunhukamwe, Brendan Taylor (wk), Sikandar Raza, Regis Chakabva, Richmond Mutumbami, Tinotenda Mutombodzi, Donald Tiripano, Wesley Madhevere, Chris Mpofu, Carl Mumba