Watch: Nadal schools young Russian, awaits Federer

World number one Rafa Nadal provided Russian teenager Andrey Rublev with a tennis lesson on Wednesday, racing into the semi-finals of the U.S. Open with a ruthless 6-1 6-2 6-2 win.

The 19-year-old, who grew up idolising Nadal and had the Spaniard's poster pinned up on his bedroom wall was smiling from ear-to-ear as he posed for pre-match photos on Arthur Ashe Stadium court with his hero.

That would be the highlight of an eye-opening afternoon for the Russian youngster as Nadal showed no mercy during a one hour, 37 minute thrashing.

Once the match started it did not take long for Rublev's grin to disappear. It was replaced by scowls and frustration as the Russian angrily yelled at himself for missed shots and occasionally slapped at his leg with a clenched fist.

Nadal, still stinging from a third-round upset by 18-year-old Canadian Denis Shapovalov in Montreal in August and with a spot in the semi-finals and a possible showdown with rival Roger Federer on the line, was fully focused on the task at hand.

While fans were still filing into Arthur Ashe, Nadal was wrapping up a clinical first set in 23 minutes.

Rublev offered some resistance to start the second but it was brief, Nadal...