Ganso out of Brazil friendlies

 　　RIO DE JANEIRO, May 23 (Xinhua) -- Midfielder Paulo Henrique Ganso will undergo surgery on his right knee, forcing him out of Brazil's upcoming friendlies against Denmark, the US, Mexico and Argentina.

　　The 22-year-old will play for Santos against Argentina's Velez Sarsfield in Thursday's Copa Libertadores quarterfinal second leg before having arthroscopic surgery on Friday, Estadao reported.

　　It is expected Ganso will be sidelined for 20 to 30 days, meaning he could be fit to play in the Copa Libertadores semifinal second leg on June 21, should Santos qualify.

　　Ganso reportedly chose to have the operation sooner rather than waiting until after the Copa Libertadores tournament to be fit for the London Olympics.

　　The procedure will be carried out by Santos doctor Jose Ricardo Pecora, who will remove residue¹ from two previous operations on the knee.

1 residue   

n.残余，剩余，残渣

参考例句：

• Mary scraped the residue of food from the plates before putting them under water.玛丽在把盘子放入水之前先刮去上面的食物残渣。
• Pesticide persistence beyond the critical period for control leads to residue problems.农药一旦超过控制的临界期，就会导致残留问题。