Olympiakos rejoined Panathinaikos and Atromitos on top of the Super League table on October 23 after beating Panionios 3-0 away, but OFI grabbed the win of the weekend by defeating Europa League challenger AEK 3-1 at home.
Two goals by Rafik Djebbour and one by Kevin Mirallas secured Olympiakos its first away win in the capital for almost a year-and-a-half, taking it to 13 points, level with Panathinaikos and Atromitos, although the latter has played two more games than the other two.
Notably, Panionios fans had a standing ovation in store both for Djebbour, a former Panionios player, and for Ariel Ibagaza, who played a part in all three Olympiakos goals.
OFI stunned AEK thanks to a brace by former Greece striker Vangelis Mantzios and a goal by Chumbinho to climb to the seventh spot with eight games from five matches. AEK had temporarily reduced the arrears through veteran Nikos Liberopoulos.
Aris and PAOK shared a 1-1 draw in a Thessaloniki derby that was passionate if not entertaining at the Kleanthis Vikelidis stadium.
Nikos Lazaridis gave Aris the lead through a header at the third minute, with PAOK equalizing thanks to Thanasis Papazoglou, who headed the ball in at the 48th.
PAOK is now fourth with 11 points from seven games, while Aris is 12th and still without a win in five games.
Kerkyra and Panetolikos were not in action this weekend.