All four teams in Group E are capable of earning qualification to the round of 16 depending on their results in the final games, but Slovakia and Spain have the chance to put one another out of the tournament entirely.
Slovakia are currently sitting on three points heading into the deciding round of fixtures, following their opening 2-1 win over Poland thanks to a Wojiech Szczesny own goal and Milan Skriniar's bullet header.
They were then beaten by Sweden most recently, with a late penalty from Emile Forsberg enough to separate the sides.
Spain on the other hand have managed to dominate both fixtures they've played in but are yet to earn themselves a victory. A 0-0 draw with Sweden in the opening game was followed by a 1-1 draw with Poland, when Alvaro Morata's goal was cancelled out thanks to Robert Lewandowski's fine header.
A win for either side would see them guarantee one of the top two places in the group, while a draw would likely see Slovakia edge through and Spain miss out as one of the best third-placed teams with just three points from three games.
Sergio Busquets is back in training for the 2008 and 2012 European champions after missing the first two games following his positive COVID-19 test before the tournament started.
Alvaro Morata is likely to start up front once again after scoring his first tournament goal following a misfiring first game, as Manchester City winger Ferran Torres could return to the lineup on the wing after being dropped for the Poland fixture.
Denis Vavro has tested positive for COVID-19 in the Slovakia camp and will miss the game, while midfielder Ivan Schanz is ruled out through injury once again.
Marek Hamsik is likely to lead from his usual number ten position but Slovakia will be banking on Newcastle goalkeeper Martin Dubravka and Inter defender Skriniar being on top of their game to hold off the Spanish attack.
How to watch Slovakia vs Spain
The crunch Group E game will take place in Seville, Spain, at the Estadio de la Cartuja on Wednesday June 23.
ITV will be broadcasting the game on free-to-air television, with coverage starting at 4:30pm for the 5pm kick-off.
The game will also be streamed live on ITV Hub as well as being available in full after the game ends.
Who will progress from Group E? Have your say below.
Who is in charge?
Dutch referee Bjorn Kuipers will be the man with the whistle for the game, accompanied by his assistants Sander van Roekel and Erwin Zeistra. French official Stephanie Frappart will be the fourth official, while VAR will be done by Pol van Boekel.
Kuipers has refereed 14 previous European Championships games and was also the referee during the 2018 Europa League final and 2014 Champions League final.
He was the referee during Belgium's 2-1 win over Denmark during match day two earlier in Euro 2020, where he handed out three yellow cards.
What has been said?
Slovakia manager Stefan Tarkovic told UEFA.com: "Sweden and Poland were the favourites in our matches against them, but Spain are top favourites and not only in our group but in the whole tournament. We must prepare well for the match. I still believe we can be successful."
Defender Tomas Hubocan also spoke of his nation's chances in the game, claiming he hopes to take inspiration from Slovakia's famous win over Spain back in 2014.
"There will be huge drama in our group. There are lots of permutations before the final games. It will also be really interesting for the fans and I'm sure they will enjoy such a close finish. I would be very glad to beat Spain again as we did in 2014 in Žilina, to be able to feel that euphoria again on Wednesday."
Chelsea and Spain defender Cesar Azpilicueta has yet to feature in the tournament, but believes his country can use their hunger from previous results to go through in this one.
"The team have lots of hunger to get on with winning against Slovakia. We wish we'd got more points. That's not the reality of the situation, but it's crucial in football to depend on yourself. We're at home, it's like a knockout game, and there are things we are doing well but other aspects we know we must improve."
Odds
Slovakia - 15/1
Draw - 11/2
Spain - 1/5
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