While Welsh aims of a top-two finish realistically rely on winning each of their last three matches, their Croatian counterparts remain favourites to book a direct ticket to Germany despite suffering a rare defeat in midweek.
Match preview
Although an alternative route remains open, a mixed series of results in European Championship qualifying so far has left Wales playing catch-up to Group D front-runners Turkey and Croatia.
With five games played, Rob Page's side sit fourth in the table, level on points with Armenia, and three behind second-placed Croatia.
Both Wales and their next visitors have one game in hand on the other nations in a finely-balanced section, and it will play out before a packed stadium in the Welsh capital on Sunday evening.
After Croatia slipped up at home to Turkey on Thursday, the Dragons could still sneak into Group D's top two, but it may take victory this weekend followed by wins over both Armenia and Turkey next month to qualify automatically.
If Wales do fail to finish higher than third, they could still make it to next summer's finals via a playoff in March, and the 2028 co-hosts took a similar path to Qatar 2022.
However, following a 4-0 friendly defeat of Gibraltar in midweek, Page will still hope his team can sweep aside memories of June's home defeat to Armenia and pull off an upset against the World Cup bronze medallists.
Group D's top two clashed in the Croatian city of Osijek on Thursday evening, with both teams sitting on 10 points apiece; however, Croatia had both a game in hand and the psychological edge from winning in Turkey a few months earlier.
Due to appearing at the most recent UEFA Nations League finals, Zlatko Dalic's side had played one match fewer but occupied top spot on goal difference and were yet to taste defeat in their attempt to reach a sixth straight Euros.
Indeed, Croatia had not been beaten at home in a European Championship qualifier before Turkey came to town under new coach Vincenzo Montella, but after Baris Alper Yilmaz made the most of Dominik Livakovic's mistake in the 30th minute, the hosts were unable to recover.
After suffering several close calls and having a penalty award overturned via a VAR review, the Kockasti were beaten, so if they want to avoid needing several points from November fixtures against Latvia and Armenia, victory in Wales is now a must.
World Cup runners-up in 2018 and semi-finalists last year, Croatia are ultimately aiming to recover from their latest near-miss in the Nations League and lift the trophy in Germany next summer, which would prove a fitting send-off for some of their established stars.
First, though, Luka Modric and co will seek a third consecutive away win in Group D - a result that would put them six points clear of Wales.
Wales Euro Champ Qualifying form:
D
W
L
L
W
Wales form (all competitions):
W
L
L
D
W
W
Croatia Euro Champ Qualifying form:
D
W
W
W
L
Croatia form (all competitions):
W
W
L
W
W
L
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Team News
After experimenting with an unfamiliar starting lineup against Gibraltar on Tuesday night, Wales will naturally revert to their strongest available XI this weekend.
Captain Aaron Ramsey and Tottenham forward Brennan Johnson are the Dragons' most notable injury absentees, and the latter's clubmate Ben Davies will wear the armband in Ramsey's absence.
Having bagged a first-half brace in midweek, Kieffer Moore can be hopeful of keeping his place up front, with support provided by Daniel James and Harry Wilson.
Croatia, meanwhile, have a handful of players missing again, as Ivan Perisic is out long-term with an ACL injury, joining first-choice striker Andrej Kramaric and Feyenoord winger Luka Ivanusec on the sidelines.
After deputising for the latter on Thursday, Fiorentina's Josip Brekalo could start again, but Zlatko Dalic is likely to make some changes in order to freshen up a team beaten at home last time out.
Wolfsburg midfielder Lovro Majer and forward duo Nikola Vlasic and Bruno Petkovic are all in contention for promotion from the bench.
Wales possible starting lineup:
Ward; Mepham, Rodon, Davies; Roberts, James, Ampadu, N. Williams; Wilson, James; Moore
Croatia possible starting lineup:
Livakovic; Stanisic, Sutalo, Gvardiol, Sosa; Modric, Brozovic, Kovacic; Vlasic, Petkovic, Brekalo