The Italian outfit earned a 4-1 victory in Poland last week, putting them on the brink of progressing closer to repeating the feat of fellow Serie A team Roma last season.
Match preview
On Monday night, Fiorentina managed to extend their unbeaten record in Serie A to eight matches as they recorded a 1-1 draw at home to Atalanta BC.
The result did little for the club's top-six hopes - they remain seven points adrift of their most recent opponent - but Vincenzo Italiano will feel that their best chance of European qualification for 2023-24 is through the cup competitions.
As well as being 2-0 ahead of Cremonense in their Coppa Italia semi-final, I Viola hold a commanding advantage in this tie, Fiorentina scoring three times either side of half time to run out 4-1 victors in Poland last Thursday.
That represented the third away European fixture in succession where Fiorentina have scored four goals, while their winning streak in this competition now stands at nine games.
Although Italiano will not be viewing this game as a formality, there are likely to be bigger tests to come for Fiorentina, with every sign that they could pass each one.
From Lech Poznan's perspective, they will feel like they have over-achieved to reach the last eight, coming through three qualifying rounds to go deep in this competition.
As many as 17 matches have already been played, yet John van den Brom's team have only prevailed on five occasions in 11 attempts since the start of the group stage.
To their credit, their only defeats have been to Villarreal and Fiorentina, but the Railwaymen look destined to focus on domestic matters for the rest of the season.
On that front, they sit in third position in the table, nine points adrift of second, and it is arguably more important that they fend off their rivals in the race for bronze rather than negotiating more matches in this competition.
Fiorentina Europa Conference League form:
W
W
W
W
W
W
Fiorentina form (all competitions):
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D
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D
Lech Poznan Europa Conference League form:
W
D
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L
Team News
Having missed out versus Atalanta due to injury, Sofyan Amrabat may sit out this contest or only be named among the Fiorentina replacements.
Luca Ranieri, Giacomo Bonaventura and Josip Brekalo could all return to Italiano's starting lineup after dropping to the substitutes' bench earlier in the week.
Luka Jovic, who is joint top goalscorer in the competition alongside teammate Arthur Cabral, may be restored to the attack having remained unused on Monday.
Meanwhile, Van den Brom is unlikely to overly tinker with his Lech Poznan side, despite their capitulation during the first leg.
Afonso Sousa could return in a creative role, but veteran Scottish left-back Barry Douglas is expected to stay on the bench.
Fiorentina possible starting lineup:
Terracciano; Dodo, Milenkovic, Ranieri, Biraghi; Mandragora, Bonaventura, Barak; Gonzalez, Jovic, Brekalo
Lech Poznan possible starting lineup:
Bednarek; Pereira, Milic, Satka; Skoras, Kvekveskiri, Velde, Sousa, Rebocho; Marchwinski, Ishak
We say: Fiorentina 3-1 Lech Poznan (Fiorentina to win 7-2 on aggregate)
Having played as recently as Monday, we do not necessarily expect Fiorentina to be at their best in the second leg. Nevertheless, their superior quality and strength in depth should see them through this tie in comfortable fashion.