In a tremendous blow to a perennial Turkish Airlines Euroleague contender, Montepaschi Siena swingman Rimantas Kaukenas will be out indefinitely due to a knee injury that requires surgery, the club confirmed Tuesday. Kaukenas was injured in an Italian League game over the weekend against Vanoli Braga Cremona. He drove to the basket late in the second quarter, drew a hard foul and fell on his left knee. Kaukenas couldn't play in the 2008 Final Four after missing five months with an anterior cruciate ligament injury to the same left knee. After medical consultations on Monday and Tuesday, doctors decided that Kaukenas, 34, will need reconstructive surgery. The date of the operation will be decided after further evaluation, the club said. So far this season, Kaukenas had averaged 14.5 points on 64.3 three-pointers, 2.2 rebounds and 2.5 assists in six Turkish Airlines Euroleague games. He scored in double digits in each of those games. Montepaschi likely will rely on three-time Alphonso Ford Trophy winner Igor Rakocevic to make up for the scoring that Kaukenas provided until now. Kaukenas, the only player with his jersey retired in Montepaschi's history, returned to the Siena last season to help the team qualify for the Turkish Airlines Euroleague Final Four, where it finished third, and to win its fifth consecutive Italian League title.