The transfer window has seen a mass exodus from St Mary's Stadium, with Rickie Lambert, Adam Lallana, Luke Shaw, Calum Chambers and Dejan Lovren all departing the Premier League club.
There has been much media speculation that Schneiderlin - and possibly Jay Rodriguez - are set to join former coach Mauricio Pochettino at Tottenham, with the France international hinting that he wanted a move.
Ahead of their friendly with Bayer Leverkusen on Saturday, new manager Ronald Koeman revealed that Schneiderlin would not be considered for selection, but that the midfielder would remain at the club.
"The situation is difficult, the player makes it difficult," Koeman said.
"I spoke to him with our chairman [Ralph Krueger] and the situation has not changed - we don't sell Schneiderlin and he has to accept that.
"Tomorrow he is not in the squad. He said he is not physically and, even more, mentally prepared for tomorrow.
"On one side I can understand that. We told him to take the weekend off and think about the situation.
"He will continue as a football player of Southampton. Now it is up to him."
In an attempt to fill the void left by the numerous departures, Southampton have completed permanent moves for Dusan Tadic and Graziano Pelle, while Ryan Bertrand and Saphir Taider have joined on loan.
