Borussia Dortmund suffered a double injury blow days before the start of the Bundesliga with midfielder Oliver Kirch ruled out for two months and Ji Dong-won set to miss at least four weeks, the club said yesterday.

Last season’s Bundesliga runners-up, who open their campaign against Bayer Leverkusen on Saturday, will be without Kirch for at least eight weeks with a thigh muscle injury, they said in a statement.

His South Korean team-mate, who joined from Augsburg this season, will be out for an estimated four weeks with a thigh muscle tear.

Both players were injured in training on Tuesday afternoon and underwent checks in a Dortmund hospital yesterday that confirmed their injuries.

Dortmund are also competing in the group stage of the Champions League, starting in September.

Elsewhere, Switzerland goalkeeper Diego Benaglio an-nounced his retirement from international football, three weeks short of his 31st birthday and with 61 caps to his name.

Although not considered old in goalkeeping terms, Benaglio said he was “not the youngest” and wanted to concentrate on his career with Wolfsburg.