Kei Nishikori is closing in on a successful title defense at the Barcelona Open. He is through to the semi-final stage of the tournament, where he will next come up against intriguing foe Martin Klizan. This is just their second meeting on the professional tour, with the Slovak leading the head-to-head series 1-0. His win was a recent one – a straight sets victory over Nishikori in the opening round of the 2014 French Open, which sets up an intriguing berth for Saturday.

The Japanese No. 1 reached the final four in Barcelona with a three set victory over Roberto Bautista Agut. He defeated the Spaniard 6-2, 3-6, 6-1 in a rollercoaster meeting. Nishikori struck five aces, 25 winners and converted four break points to finish the match in one hour and 41 minutes of court time.

“I’m really happy with the way I’m playing right now, especially in the third set,” said Nishikori. “It was a really tough match.”

Nishikori will next come up against Martin Klizan, who only needed straight sets to oust another Spaniard, Tommy Robredo. He defeated the 2004 champion 7-6(5), 6-4 in an impressive performance overall. He withstood eight aces, won 89% of his first service points and saved all six of the break points he faced to close out the match in one hour and 40 minutes.

This is just the second time that these two players will meet on the ATP World Tour and it is certainly set to be an intriguing encounter marked by a potential upset. Klizan holds a win against the Japanese No. 1 and US Open runner up at the clay court Grand Slam last season, and a dominant one at that. It will be interesting to see how Nishikori handles that memory as he attempts to avenge that loss and bring the head-to-head series to equal terms.