Three goals in the final 15 minutes - plus a stoppage-time sending-off - made for an incredible climax last week, and the teams now reconvene in Istanbul.
Match preview
Held to a dramatic 2-2 draw against Zalgiris in their first step on the path to Champions League qualification, Galatasaray's hopes of progressing from the second qualifying round remain in the balance after events in Vilnius last Tuesday.
Neither team was able to find the net in a relatively even first half, but the Lithuanian champions broke the deadlock just after the break, before Gala pulled level when Abdulkerim Bardakci headed home a 75th-minute equaliser.
Just three minutes later, the visitors seized the lead when Halil Dervisoglu struck from close range, but Zalgiris produced a stunning stoppage-time reply through Donatas Kazlauskas, who then stripped off his shirt in celebration and was promptly shown a second yellow card.
With the winner of the sides' tie set to face either Ludogorets or Olimpija Ljubljana in the next round - after which the playoffs for group-stage entry will be staged - there is still plenty to play for in Istanbul.
Galatasaray bounced back from a terrible 2021-22 campaign to claim their 23rd Super Lig title last term, finishing eight points ahead of city rivals Fenerbahce to reclaim top spot after a four-year drought; earning a Champions League qualifying place in the process.
The new domestic season is not scheduled to start until mid-August, and alongside their first-leg slip up last week, Gala have recorded just one win from four pre-season matches.
Okan Buruk's side - who surged to the Super Lig summit with a streak of six consecutive wins across May and June - now face a tricky test on home turf, against a team with nothing much to lose after a spirited showing in Lithuania.
This summer, Zalgiris have already overcome North Macedonian minnows Struga in the first qualifying round, winning 2-1 on aggregate, having earned another shot at the big time by lifting their third successive A Lyga title.
Though they finished some 21 points clear of runners-up Kauno Zalgiris last term, the Kaunas-based club currently trail Panevezys by six points after 24 rounds of the 2023 campaign.
Perhaps distracted by their upcoming trip to Turkey, Vladimir Cheburin's side were beaten 2-1 by the A Lyga leaders on Sunday, ending a 12-game unbeaten run in all competitions which dated back to the middle of May.
If they are to avoid demotion to the Europa League qualifiers, Zalgiris must avoid another defeat on Wednesday evening, when they kick off as underdogs at the infamous Ali Sami Yen.
Galatasaray Champions League form:
D
Galatasaray form (all competitions):
W
L
W
D
L
D
FK Zalgiris Champions League form:
D
W
D
FK Zalgiris form (all competitions):
W
D
L
D
W
D
Team News
Although Galatasaray have now wrapped up Mauro Icardi's return to the club from Paris Saint-Germain on a three-year contract, the Argentine striker is not yet registered for their Champions League campaign.
Ivorian winger Wilfried Zaha is also unavailable, so Dries Mertens, Nicolo Zaniolo, Kerem Akturkoglu and Baris Alper Yilmaz will all vie for selection in the final third.
Lucas Torreira is set to be sidelined again, due to an injury sustained in pre-season, leaving Sergio Oliveira to compete with Fredrik Midtsjo for a spot alongside Berkan Kutlu in central midfield.
Meanwhile, Zalgiris will be without first-leg hero Donatas Kazlauskas, who must serve a suspension for being dismissed following his last-gasp leveller in Lithuania.
After making a number of changes at the weekend, when they lost a long unbeaten record, the visitors should recall several familiar faces, including front pair Adama Fofana and Mathias Oyewusi.
Former Rennes reserve Edvinas Gertmonas captains the side from between the posts, starting behind a probable 4-4-2 formation.
Galatasaray possible starting lineup:
Muslera; Boey, Nelsson, Bardacki, Karatas; Kutlu, Oliveira; Zaniolo, Mertens, Akturkoglu; Yilmaz
FK Zalgiris possible starting lineup:
Gertmonas; Pavelic, Hnid, Vucur, Bopesu; Buff, Gorobsov, Kendysh, Golubickas; Fofana, Oyewusi