Big-serving Nick Kyrgios won his first career title with a 6-2, 7-6 (3) victory over fourth-seeded Marin Cilic of Croatia in the Open 13 final Sunday. Kyrgios closed out the match with his 17th ace to cap a dream week for the 20-year-old Australian, who didn't lose a set and was unbroken in 47 games. Ranked 41st, he beat two top-10 players in No. 10 Richard Gasquet and No. 8 Tomas Berdych. It was only Kyrgios' second tournament of the year. He lost to Berdych in the third round of the Australian Open in January and was forced to withdraw from Rotterdam last week with an elbow injury. "I didn't really expect to win this title this week after having a couple of weeks off," said Kyrgios, who lost his only previous final on outdoor clay last year in Estoril, Portugal. In the semifinals, Cilic cruised past local favorite Benoit Paire 6-2, 6-7(3), 6-3 and Kyrgios eased past Berdych 6-4, 6-2. Nadal beaten Pablo Cuevas and Guido Pella will face off in the final of the Rio Open after beating highly favored opponents in the semifinals to get there. Cuevas upset Rafael Nadal — who used to be unbeatable on clay — 6-7 (6), 7-6 (3), 6-4 Saturday. It was the Uruguayan's first victory over Nadal in three attempts, and he finished off the match with an ace. Nadal, the 14-time Grand Slam winner, was also beaten in the semifinals in Buenos Aires a week ago, also on his favorite clay surface. "I'm really happy because Rafa is a great player," Cuevas said. "I came out here thinking I could win, and I knew I had to stay relaxed, which I was able to do for almost the entire match." Pella won over rising Austrian star Dominic Thiem 6-1, 6-4. Thiem won a tournament in Buenos Aires a week ago, beating Nadal in the semifinals, and had won eight straight matches before the loss. In the women's semifinals, Shelby Rogers of the United States defeated Sorana Cirstea of Romania, 6-4, 6-4, and Francesca Schiavone of Italy won over Petra Martic of Croatia, 6-3, 6-3. Rogers and Schiavone meet in Sunday's final. Querrey dumps Del Potro Juan Martin del Potro's return to tennis fell short of a fairytale ending Saturday as the Argentine lost to American Sam Querrey 7-5, 7-5 in the semifinal of the Delray Beach Open. Querrey will face Rajeev Ram in the final after the American upset fourth seed Grigor Dimitrov 6-4, 6-3 in the other semifinal. The 31-year-old Ram won his only other career finals he has played, in Newport in 2009 and last year. He beat Querrey in ‘09 to claim his first tour-level title. The former US Open champion Del Potro made his comeback at Delray Beach after an 11-month layoff following two surgeries on his left wrist. He had looked strong in his run to the semi-finals but Querrey checked his momentum by breaking his powerful serve in each set at 5-5 — the only two breaks of the match. Del Potro, 27, was aiming to recapture his magic at Delray Beach where he enjoyed comeback success by winning the 2011 title after fighting his way back form wrist surgery. Former world No. 4 Del Potro, who stunned none other than Roger Federer in the 2009 final at Flushing Meadows, has been frustrated by a succession of injuries since his sole Grand Slam title. Ranked outside the top 1,000 at Delray Beach, he showed flashes of his old form, displaying good court coverage and growing confidence in his groundstrokes throughout the week save for two poor service games against Querrey.