Mesut Ozil will miss Arsenal's clash against Olympiacos as his wife, Amine Gulse, is due to give birth to their first child.
The 31-year-old married former Miss Turkey last year, in June.
Ozil will stay behind while his colleagues travel to Athens, Greece, for the Europa League last-32 first leg.
The playmaker has made 20 appearances in all competitions this season but has been given permission by Mikel Arteta to stay behind for the European encounter.
Lucas Torreira has also not travelled with the club. The midfielder is currently ill but could still fly out to Athens if he recovers in time. The Uruguayan will be assessed over the next 24 hours.
January loan signing Pablo Mari has travelled, however, and is available for selection.
The 26-year-old was recruited from Flamengo and, if he impresses, could stay beyond the summer.
Mari was joined in January by Cedric Soares, who also arrived on loan. He is struggling with left knee issue and should to return to training at the end of the month.
Unlike Mari, the Southampton full-back is expected to return to his parent club at the end of the season.
Kieran Tierney and Calum Chambers remain sidelined.
