The move is designed to favour 2002 Wimbledon champion Lleyton Hewitt and this year's runner-up Mark Philippoussis.
Nadal will meet defending champion Guillermo Coria in the final of the Monte Carlo Masters.
The fifth seeded pair defeated Spaniards Juan Ignacio Carrasco and Juan Carlos Ferrero 6-3, 6-3, 6-4
World No 5 David Ferrer beat unseeded Ukrainian Alexandr Dolgopolov 6-1 3-6 6-4 to win the Valencia Open for the third time on Sunday, claiming his sixth ATP World Tour title this year.
The defending champion was beaten by wildcard compatriot Alex Correjta in 69 minutes in the Monte Carlo Masters.
Indian doubles pair of Yuki Bhambri and Saketh Myneni put up a valiant fight before going down to Alejandro Davidovich Fokina of Spain and Adrian Mannarino of France in a three-setter.
In the space of a few short months, Villarreal's season of promise has been transformed into a battle for La Liga survival after their elimination from the King's Cup by third-tier opposition and the subsequent dismissal of their coach.
The two former world number ones and French Open champions traded blows and counter-punches for two hours 48 minutes.
Nadal also won through to the final of the doubles with fellow-Spaniard Feliciano Lopez at the Barcelona Open.
Images from the opening day of the Wimbledon tennis championships in London, on Monday.
Former world number one Carlos Moya confidently leads another Spanish assault on the red clay of Roland Garros next week.
Both countries took a 2-0 lead over The Netherlands and Argentina respectively in their Davis Cup World Group quarter-finals.\n\n
Doubles specialists Michael Llodra and Julien Benneteau combined to fire France into the quarter-finals of the Davis Cup Saturday with a battling four-set win over Germany's Philipp Kohlschreiber and Christopher Kas in Toulon. The victory gave the nine-times winners an unbeatable 3-0 lead in the best-of-five tie and set up a last-eight clash against champions Spain or Switzerland in July.
World number one Rafael Nadal laboured into the third round of the Monte Carlo Masters while Roger Federer had a smooth start to his campaign on Wednesday.
Robredo joins compatriots Carlos Moya, Juan Carlos Ferrero and his next opponent, holder Albert Costa, in the last eight.
Juan Carlos Ferrero beat Filippo Volandri 6-4, 6-4 at the Barcelona Open to extend his winning streak to nine games.
Andy Murray spared his nearest and dearest another traumatic day out at Wimbledon as he made serene progress to join Roger Federer in the semi-finals of the grasscourt championships on Wednesday.
American Andy Roddick has pulled out of the French Open because of a shoulder injury, organisers said on Thursday.
Singles wins for Botic Van de Zandschulp and Tallon Griekspoor sparked a party amongst an army of orange-clad Dutch fans inside the Jose Maria Martin Carpena arena.
Rohan Bopanna and Aisam-Ul-Haq Qureshi's run at the Monte Carlo Masters ended on Saturday, when they were beaten in the semi-finals. The sixth seeded India-Pakistan duo lost to unseeded South Americans Juan Ignacio Chela and Bruno Soares 6-2, 6-7(4), 10-7 in a marathon match that lasted 86 minutes.
Indian rower Dattu Baban Bhokanal entered the quarter-finals of the Men's Single Sculls after finishing third in his qualifying round of the Rio de Janeiro, on Saturday.
Tens of thousands of cheering fans turned Madrid's main streets into a sea of red and waited for hours in blistering heat to see Spain's World Cup heroes pass by with the trophy on an open-topped bus.
World No 5 David Ferrer claimed his 13th career title with a 4-6, 6-3, 6-2 victory over fellow Spaniard and 2011 winner Nicolas Almagro in the Buenos Aires Open final on Sunday.
US Open champion Carlos Alcaraz has become the youngest world number one since the ATP rankings began in 1973.
Unzue is one of the two leading candidates to succeed Luis Enrique, who announced this month he will leave at the end of this season, along with Athletic Bilbao coach Ernesto Valverde.
Coria has injured a shoulder while Ferrero pulled out of next week's 2.425 million dollar event with illness.
Juan Carlos Ferrero completed a perfect two-week tour of South America with a 5-7, 6-4, 6-3 victory over fellow Spaniard and top seed David Ferrer in the Buenos Aires Open on Sunday.
28 Weeks Later is simply a ruthless, edgy and refreshingly sick piece of apocalyptic horror.
The Swiss, dreaming of capturing the only Grand Slam title to have eluded him, was drawn on Friday in the same half as several dangerous opponents, including former champion Juan Carlos Ferrero.
Tommy Robredo and Feliciano Lopez upset Israeli doubles specialists Jonathan Erlich and Andy Ram 7-6, 6-7, 6-4, 6-2 to put champions Spain through to their fifth Davis Cup final in 10 years.
Juan Carlos Ferrero was the unlikely hero for champions Spain as he rode a wave of patriotic fervour to salvage their Davis Cup hopes on Sunday.
