Dominic Thiem, the youngest member of the Top 20, saved a match point before downing defending champion Rafael Nadal in a classic 6-4, 4-6, 7-6(4) semi-final victory at the Argentina Open on Saturday.

The top-seeded Nadal opened the match by breaking Thiem’s serve, but the Austrian fought back strongly to take the first set. Nadal had looked vulnerable at times in straight-set wins over Juan Monaco and Paolo Lorenzi, and the youngster’s power and athleticism had the former World No. 1 searching for solutions.

Nadal appeared lacking in confidence, but the lefty’s resistance never waned. He snuck away with the second set by breaking Thiem in the 10^th game, when the World No. 19’s serving arm tightened just enough for Nadal to impose his will.

A back-and-forth deciding set saw Thiem save match point at 4-5, then hold off Nadal in a deciding tie-break to prevent the Spaniard from becoming the sixth player in the Open Era to reach 100 tour-level finals. The pair’s FedEx ATP Head2Head rivalry now stands at 1-1, Nadal having won their lone previous meeting at Roland Garros 2014.

The 22-year-old Austrian, seeded fifth, improves to 2-10 after dropping eight matches in a row against Top 10 opponents. He is into his fifth career ATP World Tour final, all on clay.

David Ferrer had all night to think about how to finish off Pablo Cuevas, finally winning a rain-delayed 6-4, 1-6, 6-3 quarter-final match on Saturday in Buenos Aires.

The match was slated to finish on Friday night, but a warm and humid day turned into a stormy evening, forcing tournament organizers to interrupt play midway through the first set. Ferrer and Cuevas had not met at tour-level since 2010 (2-0 for Ferrer), and the Uruguayan finally won his first set in their FedEx ATP Head2Head rivalry before succumbing.

The second-seeded Ferrer will return to the court later on Saturday to face countryman Nicolas Almagro in the semi-finals. Almagro is in top form, having upset third seed Jo-Wilfried Tsonga on Friday, but has never topped Ferrer in 15 tour-level confrontations. They will take to the court at 3:30pm local time.

Kei Nishikori may not know much about country music or barbecued ribs, but the Japanese sure knows a thing or two about winning in Tennessee.

The three-time defending champion recorded his 15^th consecutive win at the Memphis Open with a 6-2, 6-4 win over Mikhail Kukushkin on Friday night, advancing to an ATP World Tour semi-final for the first time since Toyko last fall (l. to Paire). He has not dropped a set against the Kazakh since 2012.

Nishikori will next face Sam Querrey, who also has a history of success in Memphis. The American reached the semi-finals of the Memphis Open for a third time by dismissing Yoshihito Nishioka 6-3, 6-4.

“We had a lot of close games, it was a tough match,” Querrey said. “I kept hitting through the court, and I didn’t lay off on many balls. I was happy with the way I played.

“I didn’t know much about Nishioka, except that he’s a crafty lefty. It was tough to hit the ball through him but I kept pressing.”

The Japanese lefty had expressed excitement about the prospect of facing compatriot Nishikori for the first time in an ATP World Tour event, but Querrey, who made the final four in last year’s event, gave the qualifier nothing to work with. The fourth seed fired 11 aces, saved both break points faced and closed out the win in just 72 minutes.

Querrey will have a chance to avenge last year’s 5-7, 7-6(5), 7-6(5) semi-final loss to Nishikori. The Japanese leads the FedEx ATP Head2Head rivalry 4-3, and has won the pair’s past three meetings.

Former World No. 4 Juan Martin del Potro will take on American Denis Kudla in the first round of the Delray Beach Open, which kicks off on 15 February. It will be the pair’s first tour-level meeting.

The Argentine, who only took part in two ATP World Tour events in the past year due to wrist surgery, has experienced comeback success in Delray Beach before, having won the 2011 title (d. Tipsarevic) without dropping a set after entering the draw at No. 166 in the Emirates ATP Rankings.

Del Potro is in the same half as top seed Kevin Anderson and could face third seed Ivo Karlovic in the second round.