Nadal went to three sets in back-to-back matches at the tournament for the first time ever against Ilya Ivashka in the second round and Kei Nishikori in the third round after a first round bye.
He improved significantly in quarterfinal victories over Cameron Norrie and Pablo Carreno Busta in the quarterfinals and semifinals, respectively.
Tsitsipas has yet to drop a set in Barcelona, recording straight set victories over Jaume Munar, Alex de Minaur, Felix Auger-Aliassime and Jannik Sinner. The Greek has not lost a set on clay this year (17-0) following his victory in Monte Carlo.
This is the ninth career meeting between Nadal and Tsitsipas with the Spaniard holding a 6-2 career edge. The second seed won their last meeting at this year's Australian Open, rallying from two sets down in the quarterfinals.
Both players will look to use their heavy groundstroeks to dictate play and win long rallies. For Nadal, his forehand has looked really good the last two matches while Tsitsipas has one of the best backhands in the world.
The Greek will need to serve well as Nadal is able to hold when necessary and he often gets himself out of trouble when he needs to. The Spaniard will also look to attack the Tsitsipas backhand, the weaker side for the second seed off of the ground.
Nadal uses the angles exceptionally well and the depth of his groundstrokes can pin Tsitsipas in the corner and get him off of the court, opening up the court to hit winners. The Greek can counter by trying to keep Nadal in the center of the court.
Nadal destroyed Tsitsipas in the aforementioned 2018 final and has never lost in the championship match here. The Greek is a much better player and has a tremendous amount of confidence heading into this contest.
He also can take heart in having that huge win in Melbourne, proving to himself that even if he falls behind, he can hang tough and give himself a chance to come back even if the surface is different.
That being said, this is Nadal's literal home away from home, having gone 11-0 and his last two matches looked more like the Nadal we're used to on clay. Expect this to be a lot closer than 2018, but with the same result.
Prediction: Rafael Nadal in three sets