The Dons boss successfully secured a return to Pittodrie for striker Marley Watkins, hours before the home defeat to FK Qarabag.
Next incoming to the north-east is expected to be Newcastle midfielder Matty Longstaff, despite interest from skybet Championship sides Blackburn Rovers, Huddersfield Town and Sheffield United.
The 21-year-old will be allowed to leave on loan, Steve Bruce has confirmed, and Glass looks to have returned to his former club to pick up the highly-rated middle-man, whose brother Sean has also starred for the Magpies.
Bruce said: “The kid needs to play. He’s had a really difficult year with one thing or another. Certainly, the thigh injury he picked up seemed to go on and on.
"He’s had a very good pre-season. He’s OK, but it’s something (that might happen), because the one thing he needs to do is get some games.”