Levadiakos, Panionios and Skoda Xanthi preserved their Super League status following the penultimate round of matches in the Super League on Wednesday.
Levadiakos, who were promoted last season, ensured that they will continue in the top flight in the 2012/13 campaign after Brazilian forward Chumbinho's 56th-minute goal earned them a 1-0 win at relegation-threatened Ergotelis.
Ergotelis, 14th in the 16-team standings, will now have to wait until their final match against Xanthi on Sunday to discover whether they will remain in the top flight next season.
Xanthi and Panionios made sure of their Super League future when they drew 1-1.
Along with Ergotelis, Kerkyra and Panaitolikos are the other clubs who will battle it out on the final weekend of the season to avoid joining Doxa Drama in being relegated.
On Wednesday Kerkyra boosted their survival hopes with a 4-1 win over OFI Crete, while Panaitolikos thumped Aris 5-1.
Elsewhere, champions Olympiakos Piraeus brushed aside PAS Giannena 4-0 with Kevin Mirallas taking his tally for the season to 20.