Indian Wells - David Goffin toppled 10th-seeded Marin Cilic 7-6 (7/4), 6-2 to become the first Belgian male to reach the Indian Wells semi-finals on Thursday.
The 25-year-old Goffin saved four set points in the 12th game of the first set before taking the set in a tiebreaker.
Goffin then breezed through the second set, finishing with seven aces overall in the 97-minute match at Indian Wells, one of the biggest events on the ATP and WTA calendar outside of the four Grand Slams.
"That first set was a great battle," said Goffin, who broke Cilic three times in the quarter-final. "It was tough to stay focused.
"I had a break 5-4 but it is always tough to finish a set."
Goffin advanced to the last four, where he will face either Canada's Milos Raonic or Frenchman Gael Monfils.
"I deserve to relax a little bit then be ready for the next round," Goffin said. "First I am going to enjoy this win with my team.
"I am really pleased with the way I am playing at the moment. I hope I can keep going."
Goffin also defeated Cilic on a clay court in Belgium during the Davis Cup first round on March 6.
Goffin's win over Cilic on Thursday comes less than 24 hours after he snapped a 14-match losing streak against top-10 players with a fourth-round shocker over French Open champion Stan Wawrinka.
"Even if it's Stan or even if it's Marin, I have to do my job," said the soft-spoken Belgian. "I can compete really well here. My body also is feeling good.
"I beat Marin .... so it's almost like I beat a top 10 today.
"For the future, it gives me a lot of confidence. I still don't know where I will be in the future and in the rankings, but I will try to keep improving my game to beat a lot of players like this."
Daria Kasatkina's surprising run at Indian Wells came to an abrupt halt when she was humbled 6-3, 6-2 by 18th-seeded Czech Karolina Pliskova in the women's quarter-finals.
Pliskova needed a little over an hour to oust the 18-year-old Russian, the lone teen to reach the quarters.
"It was one of the best matches what I played here so far," said Pliskova.
Pliskova, ranked 19th in the world, said the more she plays the better she gets. She is looking to not only go further at Indian Wells but boost her world ranking this week.
"It's important during the next tournaments that I have few matches behind me," she said. "I think I played some good tennis this week. I have chances to go and improve the ranking and get close to the top 10 again."
Only two of the top 12 seeds on the women's side of the draw have reached the semi-finals -- number one Serena Williams and number three Agnieszka Radwanska.
Two-time winner Williams is one of two former Indian Wells champions still in contention. Victoria Azarenka, who won in 2012, is taking the court later against Magdalena Rybarikova.
Results from the ninth day of the WTA-ATP Indian Wells tournament on Thursday (x denotes seeded player):
David Goffin (BEL x15) bt Marin Cilic (CRO x10) 7-6 (7/4), 6-2
Milos Raonic (CAN x12) bt Gael Monfils (FRA) 7-5, 6-3
Karolina Pliskova (CZE x18) bt Darya Kasatkina (RUS) 6-3, 6-2
Victoria Azarenka (BLR x13) bt Magdalena Rybarikova (SVK) 6-0, 6-0