Olympiacos kept up its perfect start to the Super League season with a 1-0 win at Atromitos.
Second-placed Panionios recorded its fourth win of the season by the same scoreline thanks to Leonidas Kampantais' 16th-minute goal against AEK Athens.
AEK had substitute Taxiarchis Fountas sent off with three minutes remaining.
Kerkyra beat OFI Crete 2-1 in the day's other match, its first win of the season coming thanks to two goals in three first-half minutes from Tassos Agritis and Dimitris Giantsis.
Brazilian midfielder Fernandinho has confirmed he wants to join Manchester City.