NEW YORK (Reuters) – Spaniard Pablo Carreno Busta said playing in the shadow of Rafael Nadal, his country’s most celebrated player, has helped to keep the pressure off him as he has quietly advanced to the semi-finals of the U.S. Open.

The softly-spoken 12th seed has yet to drop a set in the tournament having benefited from a kind draw.

He did not face a seeded player until Tuesday’s encounter with world number 33, Diego Schwartzman, who he dispatched in straight sets to reach the last four.

“Of course if you speak with some Spanish people about tennis, everybody knows Rafa. That’s true that Rafa is an incredible tennis player. He is one of the best ever,” Carreno Busta told reporters after his quarter-final match.

“Maybe it’s just easier when, in your country, Rafa has all the attention and you are without this pressure,” he added.

Carreno Busta counts the world number one not only as a good friend but also as a mentor who has helped him reach his first ever grand slam singles semi-final.

“I always try to practice with him because it’s really important to me, to be near the best players and practice with them,” he told reporters on Sunday.

“I just try to learn about how he practices, what he does after practice, before practice, after matches, before matches. I think I‘m learning a lot.”

He might benefit from picking Nadal’s brains prior to his semi-final match on Thursday, when he will face his stiffest challenge yet in either 17th-seeded American Sam Querrey or powerful South African Kevin Anderson.

If Carreno Busta manages to advance to the final, he may have to put his friendship with Nadal on hold as the 15 times major champion could be standing between him and a maiden grand slam crown.