Rafael Nadal booked his place in the third round of the Cincinnati Masters ©Getty Images

Rafael Nadal booked his place in the third round of the Cincinnati Masters as he swept aside Frenchman Richard Gasquet at the Lindner Family Tennis Center in Ohio.

The Spaniard, who will become the world number one for the first time since July 2014 on Monday (August 21) after Roger Federer withdrew from the tournament, claimed a comfortable 6-3, 6-4 victory over Gasquet.

The 31-year-old, a winner of 15 Grand Slam titles, is due to take on compatriot Albert Ramos Viñolas in round four.

"I work every day to play better," said Nadal. 

"It's obvious that was an important start for me, a good one."

Germany's Alexander Zverev crashed out of the event as he was upset by unseeded American Francis Tiafoe.

Zverev was unable to show the form which saw him beat Federer to lift the Rogers Cup last Sunday (August 13) as he slumped to a 6-4, 3-6, 4-6 defeat to the world number 87.

Germany's Alexander Zverev crashed out of the event as he was upset by unseeded American Francis Tiafoe ©Getty Images
Germany's Alexander Zverev crashed out of the event as he was upset by unseeded American Francis Tiafoe ©Getty Images

Third seed Dominic Thiem of Austria joined Nadal and Tiafoe in the fourth round as he overcame Fabio Fognini 6-3, 6-2.

Australian qualifier Ashleigh Barty was another player to earn a shock win as she proved too strong for world number nine Venus Williams.

Barty had never beaten a player in the top 10 before but held her nerve to secure a 6-3, 2-6, 6-2 victory over the 37-year-old American. 

Denmark's Caroline Wozniacki, who beat Russia's Elena Vesnina 6-2, 6-4, awaits for Barty in the third round.

Angelique Kerber of Germany missed out on the chance to move to the top of the world rankings as she lost 6-4, 1-6, 7-6 to Ekaterina Makarova of Russia.