Despite Saturday's defeat in Sweden, Slovakia have confirmed a promotion playoff for March, while Estonia sealed survival by avoiding defeat in Azerbaijan.
Match preview
Although their unbeaten record in this season's Nations League was brought to an end on Saturday night, Slovakia could still secure a spot in League B next time around.
Sweden's much-admired striker Viktor Gyokeres put the hosts ahead after just three minutes in Solna, before David Hancko equalised; however, another top-notch forward, Alexander Isak, then scored what turned out to be the winner shortly after half time.
The Falcons' first defeat was effectively sealed when captain Milan Skriniar was sent off for a second bookable offence with time running out, but a playoff place is already theirs.
Following two wins over Azerbaijan, victory against Estonia and last month's home draw with Sweden, Francesco Calzona's side have 10 points on the board, which is sufficient to guarantee a top-two finish.
Slovakia - who came so close to reaching the last eight at Euro 2024 - have proved one of the stronger sides in Europe's third tier, so they may fancy their chance of gaining promotion in March, when a playoff against League B opponents will take place.
When both teams kicked off their campaign back in September, Slovakia and Estonia played out an uneven contest in Tallinn, which they away side totally dominated in terms of possession and shot count but only ended up winning 1-0.
Since then, the Estonians have lost twice to Sweden and taken four points from rock-bottom Azerbaijan, who they visited on Saturday.
Last month, Jurgen Henn's men won 3-1 at home to their Azeri rivals, but they had to settle for a goalless draw at the weekend, when they once more let their opponents have most of the ball.
As well as confirming their League C status, a rare clean sheet was something to celebrate for the Blueshirts, who had conceded an average of two goals per game before heading east to Qabala.
Having topped their League D table in the last Nations League, Estonia have found life far tougher at a higher level; but whatever happens in Trnava, their objective has already been achieved.
Slovakia Nations League form:
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W
D
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L
Slovakia form (all competitions):
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W
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D
W
L
Estonia Nations League form:
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L
W
L
D
Estonia form (all competitions):
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L
L
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L
D
Team News
Slovakia must make at least one change to their back four on Tuesday, as inspirational skipper Milan Skriniar was sent off in Sweden and must now serve a suspension.
Cagliari defender Adam Obert is his likeliest replacement, and Francesco Calzona may be tempted to introduce fresh legs elsewhere, given that the Falcons are already confirmed in second place.
Midfield fulcrum Stanislav Lobotka has just returned from a thigh problem and could even be rested, while Euro 2024 star Ivan Schranz is also back from injury and will now hope to make the starting XI after appearing as a substitute at the weekend.
Jurgen Henn might also make changes after the long trip to and from Azerbaijan, so Alex Matthias Tamm could replace Estonia's leading active scorer Henri Anier up front - experienced forwards Erik Sorga and Rauno Sappinen were not called up.
Meanwhile, Shamrock Rovers midfielder Markus Poom faces competition from Martin Vetkal to start in the visitors' engine room, while Rocco Robert Shein should provide a link between midfield and attack.
Slovakia possible starting lineup:
Greif; Gyomber, Satka, Obert, Hancko; Duda, Lobotka, Benes; Suslov, Strelec, Schranz
Estonia possible starting lineup:
Hein; Peetson, J. Tamm, Mets, Schjonning-Larsen; Poom, Palumets; Yakovlev, Shein, Sinyavskiy; A. Tamm
We say: Slovakia 2-0 Estonia
Particularly with their home fans behind them, Slovakia will be a class above Estonia; but, with their playoff berth booked, they may step off the gas.