The 20-year-old Dominic Thiem will be presented with the biggest challenge of his young career tomorrow as he takes on Rafael Nadal on Court Philippe Chatrier.

Nadal has only lost one set in the second round at the French Open, and his early matches at the French Open are usually “David v. Goliath” types of affairs where the inevitability of a Nadal victory persists from first point to last. It is almost always inexcusable for a player to go on court believing they will lose. Against Nadal on clay, such a mindset would be difficult to criticize.

Greater players than Thiem have tried—more experienced, more battle-hardened players. Of these players, only one (Robin Soderling) has succeeded in doing what at times has seemed impossible. Despite all of this, the record will reflect, that regardless of the outcome of the match, Dominic Thiem believes he can win.

When watching Thiem, it is evident that his on-court mentality, a mentality characterized by fearlessness and a belief in the fight, is ingrained in each and every strike he delivers upon the ball. While no one would argue that tennis is just a game between a player and the ball, and not the opponent, Thiem realizes that he is the only one who can control the intent he carries with each shot that is hit.

Against Nadal, such a mentality is critical to hold on to for dear life. It’s incredibly easy to become drowned and consumed in the stream of Nadal’s heavy topspin forehands and utterly devastating patterns.

Thiem and Nadal have never played. The fact that they have never met should work in the Austrian’s favor. So many of Nadal’s helpless victims on clay are deprived of their belief and left scarred with endless memories of forehand winners and extraordinary passing shots. Thiem will have the disadvantage of having never seen Nadal’s balls in a match setting, but a blank slate ensures that he enters this match as positively as possible.

The vulnerability of Nadal during the clay season has probably been overstated, but it’s something that cannot be ignored. If this was any other year, even 2011 when Nadal lost in the finals of Madrid and Rome, the intrigue around this match wouldn’t be so high. Thiem’s ascendancy and Nadal’s relative decay will cause this to be most curious second-round match the eight-time champion has ever played in Paris.

Tactically speaking, Thiem’s sensational one-handed backhand will be the story of this match. To handle Nadal’s heavy cross-court topspin forehand, Thiem must be ready to step and drive through his single-handed weapon, much as Djokovic does with two hands. But as Roger Federer could tell you, driving through and uncoiling on a high ball off a single-handed backhand is no simple feat.

Thiem’s one-handed backhand will also need to be used to escape Nadal’s cross-court forehand pattern. Most players have trouble changing direction on Nadal’s cross-court forehand, but with Thiem’s propensity to take his backhand down the line, he should have an easier time accessing the Spaniard’s backhand.

When discussing a Nadal match on clay, the conversation is usually geared around what the other player must do. But there is one tactic that Nadal must avoid, and that is returning serve from the stands. Besides possessing crushing groundstrokes, Thiem also has a cannon-like serve. Standing 10-12 feet behind the baseline to return serve will give Thiem the initiative in far too many points, allow him to serve and volley with supreme effectiveness, and open up a bevy of angles that even Nadal can’t defend against.

It will also be important for Nadal to avoid become overly passive off the ground. Doing so will allow Thiem to thrive off high-percentage cross-court strikes and the resultant short balls.

With the way the draw has opened up, this will in all likelihood be Nadal’s toughest matchup until the quarterfinals. This is undoubtedly a bigger test than Nadal was probably expecting to have to deal with this early in the tournament. But make no mistake, he will not underestimate Thiem, and he will be ready.

This match has the potential to be great and if Thiem shows up in a big way, this crazy French Open may get even crazier.

Prediction: Nadal in five sets