The home side were crushed 4-0 last week and require a faultless showing to turn the tie around.
Match preview
Astana have not made it to the group stage of the Champions League since 2015-16, and that wait is expected to continue unless the Kazakhstan club are flawless against Dinamo.
A 4-0 defeat suffered in Zagreb a week ago means Grigori Babayan's side are fighting a losing battle heading into the game.
Making it to the second qualifying round represents progress for the Yellow and Blues, who could not better their first knockout phase opponents in 2019-20 and 2020-21.
Last season's Kazakhstan Premier League champions' preparation for Wednesday's game took a dent over the weekend when they were beaten 1-0 by out-of-form Qyzyljar, thus seeing them fall three points behind table-topping Ordabasy.
Even though they are unlikely to turn around a 4-0 deficit, stranger things have happened.
As for Dinamo, the Croatian outfit must manage the game after opening a commanding advantage in last week's encounter at Stadion Maksimir.
Despite dominating for the game's entirety — and particularly in the opening half — Igor Biscan's team did not open the scoring until Dario Spikic scored in the 35th minute, having been set up by Bruno Petkovic.
Two more first-half goals were netted by Luka Ivanusec, who scored another in the 56th minute to complete his hat-trick.
The Blues seldom fail to progress to the third qualifying round, and they are closing in on another victory as they seek a third group stage participation in the last five seasons.
Beaten once since their embryonic season's commencement — a 2-1 home defeat by Hajduk Split — Dinamo are unlikely to suffer a second on Wednesday.
Astana Champions League form:
D
W
L
Astana form (all competitions):
Dinamo Zagreb Champions League form:
W
Dinamo Zagreb form (all competitions):
L
W
W
Team News
Apart from Mikhail Gabyshev, who was forced off in the last round's first-leg encounter with Dinamo Tbilisi, Astana boss Babayan is unlikely to be forced into making enforced changes on Wednesday.
Marin Tomasov and Dembo Darboe were instrumental in sealing a turnaround against Dinamo Tbilisi in the last round, and the pair could be motivated to come up trumps again, even if a turnaround looks unrealistic this time.
The ankle injury suffered by Gabrijel Rukavina at the denouement of the left winger's breakthrough season last term still sidelines him from Dinamo action.
Ivanusec netted in the Blues' 3-0 win over NK Istra 1961 over the weekend, and the wide attacker is in a rich vein of form before Wednesday's game in Kazakhstan.
Despite scoring and assisting in the league win, Mahir Emreli may not keep his spot at centre-forward, with Petkovic returning to the side.
Astana possible starting lineup:
Condric; Hovhannisyan, Marochkin, Tomasevic, Amanovic, Vorogovskiy; Tomasov, Beysebekov, Ebong, Ourega; Darboe
Dinamo Zagreb possible starting lineup:
Livakovic; Moharrami, Ristovski, Sutalo, Mykhaylichenko; Ljubicic, Misic; Spikic, Baturina, Ivanusec; Petkovic