The Istanbul giants let a two-goal lead slip against Konyaspor as they began life under Ersun Yanal in poor fashion ahead of their tie with the Gunners
The Istanbul giants, playing their first Super Lig game under new coach Ersun Yanal, had led 2-0 at the Konya Ataturk Stadium with under 15 minutes remaining thanks to goals from Joseph Yobo and Emre Belezoglu.
However, the minnows staged a stunning comeback, first though Tomas Borek and Ali Camdali, who struck within minutes of one another, before Recep Aydin completed the victory with minutes remaining.
Emmanuel Emenike, who was re-signed from Spartak Moscow in the close season, squandered a number of chances for the visitors, while the hosts had missed a penalty prior to their revival.
Arsenal, meanwhile, also warmed up for the Sukru Saracoglu clash in far-from-ideal fashion, having a man sent off as they slumped to a 3-1 home loss to Aston Villa.
Fenerbahce entertain the Gunners at 20:45CET on Wednesday, before the two sides clash once more at the Emirates Stadium the following Tuesday.