Spanish 12th seed Pablo Carreno Busta, who has not dropped a set at the US Open, advanced to his first Grand Slam semi-final on Tuesday by defeating Argentine 29th seed Diego Schartzman 6-4, 6-4, 6-2.

Carreno Busta, the first player to face four qualifiers in any Grand Slam, booked a Friday semi-final against South African 28th seed Kevin Anderson.

“Incredible,” 12th seed Carreno Busta said. “It’s something that I always dreamed about but something I never thought was going to arrive here. It’s a great feeling.”

While legends Roger Federer and Rafael Nadal are each one win from meeting for the first time at the US Open in a potentially epic semi-final, this half of the men’s draw is guaranteed to produce a first-time Slam finalist.

“It would be fantastic to play him in the final,” Carreno Busta said Nadal. “But we have to play step-by-step.”

Carreno Busta captured the first set in 38 minutes, broke in the ninth game and held again to take the second. He broke at love on a double fault to open the third set, broke again in the seventh game and held to end it in just under two hours.

Anderson halts Sam Querrey

Anderson downed 17th-seeded American Sam Querrey 7-6(5), 6-7(9), 6-3, 7-6(7) to book a berth in Friday’s semi-finals.

Anderson, the first South African in any Slam semi-finalist since Wayne Ferreira at the 2003 Australian Open, will meet Spanish 12th seed Carreno Busta, who has not dropped a set, for a place in Sunday’s final.

“To play in one of the most famous courts in the world at night and to get through, it feels fantastic,” said Anderson.