Fernabahce's tumultuous week continued on Thursday with a stirring second half fightback in a 3-2 loss at Olympiakos to keep alive their hopes of progressing to the Europa Conference League semi-finals.

The Turkish outfit appeared to be done and dusted after an hour's play, with their Greek hosts bossing the quarter-final first leg by three goals.

Kostas Fortounis and Stevan Jovetic put Olympiakos firmly in control by half-time, with Chiquinho consolidating their advantage on 57 minutes.

But a 68th minute penalty from Dusan Tadic followed by Irfan Can Kahveci's 74th minute contribution gave Fenerbahce a lifeline ahead of next week's return leg in Turkey.

Fenerbahce went into the fixture hours after copping a 115,000 euros ($123,175) fine over their Turkish Supercup protest at the weekend.

Fenerbahce walked off the field in the opening minutes of the fixture against Galatasaray on Sunday as a protest against alleged unfair treatment.

Fenerbahce fielded an Under-19 team for the game against their Istanbul rivals. Galatasaray went ahead after three minutes with Fenerbahce then walking off in a pre-planned protest.

The Turkish Football Federation awarded Galatasaray a 3-0 win and issued Fenerbahce with the six-figure fine.

"It's time for Turkish football to be reset," Fenerbahce president Ali Koc had told a press conference before the match.

Fenerbahce are chasing their first Turkish title since 2014 and are two points behind champions Galatasaray with seven rounds to go. Fenerbahce claim they are being picked on.

They had asked for the Supercup to be postponed ahead of their Conference League quarter-final.

With their tails up they will be desperate to finish off Olympiakos on home turf next week.