Juan Martin del Potro continued to struggle since his return from injury, as the Argentine was thrashed by the sixth-seeded Feliciano Lopez of Spain in straight sets with a 6-3 6-0 scoreline, in the first round of the Japan Open.

Earlier, Del Potro lost to Olivier Rochus at the Thailand Open in his first appearance last week. On the other hand, Daniel Gimeno-Traver of Spain beat Argentina’s Eduardo Schwank with a 6-4 6-4 scoreline and seventh-seeded Dmitry Tursunov of Russia earned an easy victory over Ernests Gulbis of Latvia with a 6-3 6-4.

World no. 1 Rafael Nadal has a first-round bye in the Japan Open and the Spaniard will start his campaign against Colombia’s Santiago Giraldo on Tuesday.