Bernard Tomic's battle for form has continued with a straight sets loss to Dmitry Tursunov in the first round of the Japan Open in Tokyo.

Ranked No.39 in the world, Tomic was beaten 6-4 7-5 by qualifier Russia's Tursunov as he attempted to rebound from a disastrous second round loss at the US Open, which was followed by another poor effort in Australia's Davis Cup loss to Germany in Hamburg last month.

Tursunov won 30 of his first 33 service points on Tuesday as he claimed his first tour level victory since a first round win at the French Open in May.

Tomic was cleared of tanking by tennis officials following his US Open defeat at the hands of American Andy Roddick that was described by Australia's Davis Cup captain Patrick Rafter as "disgraceful" and tennis great John McEnroe as "a tank job".

During another disappointing performance in Hamburg, Tomic was berated for his efforts by Davis Cup coach Tony Roche.