The second half of the Euroleague’s first group stage begins tomorrow for the two Greek representatives in the continent’s top basketball club competition, with both Panathinaikos and Olympiakos finding themselves on top of their pools. Panathinaikos will host Spain’s Valencia and is likely to score its fifth win in six games at the Olympic Sports Hall in Maroussi, although it will be missing center Aleks Maric. The Australian has undergone surgery and will miss the next month’s action. Olympiakos has a more daunting task as it travels to Madrid to face Real. Coach Dusan Ivkovic’s team is aiming at its fifth win, but would also be happy with a loss whose margin is no larger than the 16 points by which it beat Real in October. Last night there was mixed news for Greek sides in the Eurocup, as Aris scored its second win in as many games when it beat Hapoel Gilboa Galil 92-83 in Israel, while PAOK succumbed to its second defeat, going down at home to Italy’s Benetton Treviso 67-62.