Australian Open semi-finalist David Ferrer failed to get past the first round at the World Indoor Tournament after being surprisingly swept aside 6-3, 6-4 by unseeded Finn Jarkko Nieminen on Tuesday.
Defending champion Serena Williams was knocked out by Jelena Jankovic in the quarter-finals of the Australian Open.
Top seed Roger Federer struggled to defeat Finn Jarkko Nieminen 7-5, 7-6 on Friday to reach the semi-finals of the World Indoor Tournament.
Roger Federer beat Finn Jarkko Nieminen 6-3, 6-4 to defend his title in Basel and top the year-end rankings.
The world No 1 will face unseeded Finn Jarkko Nieminen, who defeated 2006 Australian Open finalist Marcos Baghdatis 7-6 6-2 in the other semi-final.
The Russian was embroiled in a betting controversy after he retired from his match against Vasallo Arguello in Sopot last week.
World number seven David Nalbandian stayed on course for his first Stockholm Open title by crushing Spaniard Albert Montanes 6-4, 6-1 in the quarter-finals on Friday. The top seed from Argentina broke serve once in the opening set and three times in the second to set up a meeting with third-seeded Finn Jarkko Nieminen, who ousted Spain's Oscar Hernandez 6-1, 6-4.
Leander Paes and Lukas Dlouhy edged towards back-to-back titles as they advanced to the finals of the AIG Open in Tokyo.
American James Blake outclassed Finn Jarkko Nieminen 6-4, 6-2 to retain his Stockholm Open title on Sunday and boost his chances of appearing in the season-ending Masters Cup for the first time.
Gaudio has beaten Nadal three times out of four but the Spaniard won their most recent match in Monte Carlo this year.
The seventh seeded Thai lost to Spaniard Feliciano Lopez in the first round.
Twice champion James Blake came from behind to beat Finn Jarkko Nieminen 6-7 6-4 6-2 and book a place in the Stockholm Open semi-finals on Friday.
The Australian edged past Jarkko Nieminen 1-6, 6-3, 7-5, 6-2 in the French Open third round.
The defending champion battled back from 4-6, 1-4 down to set up a semi-final against unseeded Spaniard Nicolas Almagro, who upset 10th seed Juan Carlos Ferrero at the Barcelona Open.
The Australian third seed was too strong and too consistent for the 15th-seeded Slovak as he won in 94 minutes.
Bernard Tomic's on-court commitment has come under renewed scrutiny after the Australian played match point holding his racquet backwards in defeat to Fabio Fognini at the Madrid Open.
It is not the first time Tomic has been in trouble for not trying.
Bernard Tomic ruled himself out of representing Australia at the Rio Olympics in August due to his 'extremely busy' playing schedule.
Tatsuma Ito and Michal Przysiezny claimed the biggest wins of their careers at the Japan Open on Tuesday when the local wildcard knocked out top seed Stan Wawrinka and the Polish qualifier saved match points to beat Jo-Wilfried Tsonga.