Carlo Ancelotti's side overcame Barcelona in the semi-finals of the tournament, while Osasuna navigated their way past Athletic Bilbao to reach the final for just the second time.
Match preview
Real Madrid are not going to retain the La Liga title this season, as they currently sit third in the table, 14 points behind leaders Barcelona with five games left, and they will enter this contest off the back of a 2-0 defeat at Real Sociedad on Tuesday night.
Los Blancos have actually now lost four of their last eight league games during a disappointing run, but they can still enjoy a successful end to the season, with the team bidding to win a Copa del Rey and Champions League double.
Ancelotti's team will face Manchester City in the semi-finals of the European Cup, with the first leg of the last-four affair set to take place at Bernabeu next week.
Real Madrid's immediate focus is on the Copa del Rey final, though, with the capital giants looking to win the tournament for the first time since 2014, and a success would make it 20 trophies in the competition.
Los Blancos were 1-0 down to Barcelona heading into the second leg of their Copa del Rey semi-final at Camp Nou but managed to record a 4-0 victory to comfortably make the final, while they also eliminated Atletico Madrid in the quarter-finals and Villarreal in the round of 16, so it has been a tough run to the final.
Osasuna are undoubtedly the underdogs heading into this weekend's final, with Los Rojillos looking to win this competition for the first time in their history.
The Pamplona-based outfit made the final of the Copa del Rey in 2005, losing to Real Betis, but they have not made much of an impression in the competition since and went out in the round of 32 last term.
Jagoba Arrasate's side have beaten Fuentes, Arnedo, Gimnastic Tarragona, Real Betis, Sevilla and Athletic Bilbao to advance to the final, overcoming the latter 2-1 on aggregate in the semi-finals last month.
Osasuna will enter this match off the back of successive league defeats to Real Sociedad and Barcelona, which has seen them drop into ninth position in the table, but they are only five points behind sixth-placed Real Betis and could still claim a European spot for next season through La Liga.
Los Rojillos have not managed to overcome Real Madrid in any competition since a La Liga game in January 2011, while they suffered a 2-0 loss when the two sides last met in Pamplona back in February, but Arrasate's team can certainly take heart from some inconsistent form from the capital giants in recent weeks.
Real Madrid Copa del Rey form:
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Real Madrid form (all competitions):
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Osasuna Copa del Rey form:
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Osasuna form (all competitions):
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Team News
Real Madrid will again definitely be without the services of Ferland Mendy due to a calf problem, but the France international is the team's only confirmed absentee at this stage.
David Alaba and Luka Modric are both battling to recover from hamstring problems in time for the match, but it seems likely that the pair will be on the bench if they manage to make the squad.
Karim Benzema was rested against Real Sociedad and will be available to return here, while Vinicius Junior and Eduardo Camavinga will also be back after serving suspensions last time out.
Aurelien Tchouameni could benefit from Modric's injury problems to start in central midfield, while Federico Valverde could also play in a deeper role to allow Rodrygo to feature in the final third.
As for Osasuna, Darko Brasanac is out for the season with a serious knee injury, but Arrasate is hoping to have David Garcia and Nacho Vidal available for selection on Saturday.
Jon Moncayola will also return this weekend, with the Spaniard missing out against Barcelona in the league on Tuesday evening through suspension.
Kike Garcia, Juan Cruz, Aridane Hernandez and Moi Gomez should also all return to the XI, while Sergio Herrera has been Osasuna's Copa del Rey goalkeeper this season, and the 29-year-old should therefore feature between the sticks in Seville on Saturday night.
Real Madrid possible starting lineup:
Courtois; Carvajal, Militao, Rudiger, Camavinga; Valverde, Tchouameni, Kroos; Rodrygo, Benzema, Vinicius
Osasuna possible starting lineup:
Herrera; Moncayola, Aridane, D Garcia, Cruz; Torro, M Gomez; R Garcia, Oroz, Ezzalzouli; Kike Garcia
We say: Real Madrid 3-1 Osasuna
Osasuna have the top scorer in this season's competition in their ranks, with Kike Garcia finding the back of the net on five occasions, and we are backing Arrasate's side to score on Saturday night.
Real Madrid often pull out big performances when they need it most, though, and we are fully expecting the Spanish and European champions to navigate their way to a victory to claim the Copa del Rey trophy.