BERLIN, Sept. 30 (Xinhua) -- Hertha Berlin's Brazilian defender Lucio will be sidelined for at least six to nine months due to a serious knee injury, according to a club doctor on Sunday.

Lucio suffered the injury in a match at Schalke 04 on Friday and has had a knee surgery.

Hertha team doctor Ulrich Schleicher said it could not be ruled out that the injury could end the career of the 28-year-old who joined Hertha in the close season on a 1.75-million euro transfer from Palmeiras Sao Paulo.

"The operation was successful," Schleicher was quoted as saying.

"If everything goes well, he'll be out for six to nine months. Lucio has to been given all the time he needs to come back."

Lucio went down after a collision with Schalke's Peter Lovenkrands in the 63rd minute of the match Schalke won 1-0.