Bayern Munich might pay a high cost for missing their players who participated in the World Cup during the preparation period for the new season, coach Felix Magath said. The German champions kicked-off their preparations with only 13 players including four youngsters as the rest of the squad is still on vacation. The 24-man squad will gather just two weeks before the Bundesliga curtain-raiser when Bayern play Dortmund. "A two-week period is too few, for us this will be a handicap," Magath told German paper Kicker on Sunday. Bayern had the same problem after the EURO 2004 and the Confederations Cup in 2005 but Magath believes it is different for the Bavarian team this time. "This time we have a tough job to do. We are building a new team, a team without our former captain Michael Ballack," he said. Ballack signed for Premiership giants Chelsea before the World Cup and Bayern have now to do without their instrumental midfielder. Magath made history in 2006 when he steered Bayern to winning the domestic double for the second successive season.