ROTTERDAM (Kyodo) Feyenoord's Japanese midfielder Shinji Ono may undergo surgery after he re-injured his left ankle in a league match, the Dutch club said on its Web site Sunday.

News photoShinji Ono of Feyenoord dribbles the ball during the first-half of a Dutch League game against ADO Den Haag.

Ono aggravated an old injury to his ankle when he was fouled in the 39th minute and was substituted at halftime in his side's 2-0 defeat Sunday at ADO Den Haag. Feyenoord said after the match he will return to Japan shortly to receive examinations.

Feyenoord manager Ruud Gullit said Ono will likely have surgery, while a team doctor was quoted as saying on the website that surgery is possible depending on the results of examinations in Japan.

Ono is expected to be sidelined for about six weeks if he has surgery and is doubtful for Japan's clash at home with North Korea on Feb. 9 in their opening match of the Asian zone final qualifying round for the 2006 World Cup in Germany.

Sunday's loss to lowly Den Haag left Feyenoord in fourth place in the Dutch league going into the winter break on 31 points from 17 matches, 11 points behind leaders AZ Alkmaar and PSV Eindhoven.