Former French Open champions Carlos Moya and Gaston Gaudio both lost in the opening round of the Madrid Masters.
Former world number one Moya is now 43rd in the world rankings
Moya committed 31 unforced errors in his 6-3 6-2 defeat to Argentina's Juan Ignacio Chela.
Gaudio won the opening set 6-4 against Chile's Nicolas Massu but after losing the second 3-6 the Argentine retired with a stomach problem.
Mardy Fish defeated Xavier Malisse 5-7 6-3 7-5 to set up a meeting with defending champion Rafael Nadal.
Frenchman Sebastian Grosjean of France claimed a fourth win in five meetings over Sweden's Jonas Bjorkman winning 6-4 7-5.
The ATP said on Monday it wants China to host a major combined men's and women's tournament in place of the end-of-season men's Masters Cup, which it hopes to
bring back to Europe in the future.
Tour executive Etienne De Villiers said the ATP also wanted to add a combined tournament to the European calendar in the period leading up to the French Open in May - Madrid, Rome or Monte Carlo are the most likely venues.
De Villiers also explained that the organisation was
finalising plans to introduce round-robin formats and Sunday
starts at a number of tournaments next year as a way of ensuring that big-name players remain throughout the week.