Olympiakos’s dreams of challenging longtime rival Panathinaikos for the Greek Basketball Championship took a hit on Saturday when their top off-season signing, shooting guard Arvydas Macijauskas, ruptured his Achilles tendon during a friendly match. Macijauskas’s left foot somehow jammed on the floor during the match, played in Italy, and he immediately fell down writhing in pain. The extent of the damage was discovered yesterday when the team’s doctor examined him in Athens. The tests revealed a complete tear. Macijauskas will be operated on today and, if rehabilitation goes as expected, will start light training in February. Olympiakos had expected the 26-year-old shooting guard to be their main offensive weapon this season. Coach Pini Gerson has asked that the team sign a replacement shooting guard for the season. At this point, however, no player of Macijauskas’s caliber is available on the transfer market. It is said Olympiakos will make a request for Maroussi player Alexis Kyritsis on a loan for one year for a sum of around 300,000 euros. Macijauskas has the biggest contract among Greek League players, earning 2.2 million euros per season.