Rafael Nadal
Nadal faces tricky semi-final test on Friday Reuters

Fourth seed Rafael Nadal takes on sixth seed Dominic Thiem in the Men's singles semi-final of 2017 French Open at Roland Garros Stadium on Friday.

The two players will face each other for the fourth time on clay this season. Nadal won the first two meetings - Madrid and Barcelona final, but Thiem fought back with a comfortable win over the Spaniard in the quarter-final of Rome Masters. Given their current form, there is very little to choose between the two, who have had dominant run to the last-four stage.

Nadal has hardly been tested on European clay so far in this season. However, the only player to have beaten him on the dirt is his semi-final opponent, Thiem, who is heading into the clash on the back of a dominating straight set win over world number two Novak Djokovic in the quarter-final on Wednesday.

Thiem was at his absolute best, playing aggressively even when pushed away from the baseline. The Austrian was untroubled after he won the first-set tiebreaker enroute to his 7-6(5), 6-3, 6-0 win over the defending champion. The world number nine will be high on confidence and is expected to make things difficult for Nadal, who is eyeing a historic 10th title in Paris.

The key to Thiem's success in Rome was the way he was able to win points of his first serve. The 23-year-old won 68% of his first-serve compared to Nadal's 55% and was also hitting winners at will, just like the way he did against Djokovic yesterday. It was an ordinary performance from the Spaniard, who might have been tired after having won three titles on the trot on the dirt.

However, the quarter-final exit in Rome might have come as a blessing in disguise for Nadal as the rejuvenated Spaniard has been decimating his opponents enroute to the semi-final. On Wednesday, his opponent Pablo Carreno Busta retired when he was trialing 2-6, 0-2 with an injury, thereby giving the nine-time champion more time to rest ahead of a tricky quarter-final test.