The Manchester City captain was back on the bench for Friday's 1-0 loss to Poland, which stretched Die Mannschaft's miserable winless run to three matches.
Gundogan was kept in bubble wrap following the Champions League final, but the 32-year-old should be in contention for a start on Tuesday, where Flick is likely to ring the changes once again.
Joshua Kimmich is in line for a rest and may be demoted to allow Gundogan to return, and the same can be said for Emre Can as Leon Goretzka pushes to return to the engine room.
As is the case with Gundogan, Inter Milan's Robin Gosens arrived late due to his Istanbul commitments, but the wing-back is a contender to displace Benjamin Henrichs on the left-hand side, while Marius Wolf should threaten Jonas Hofmann's spot on the opposite flank.
Changes should not be limited to the engine room, as Niclas Fullkrug and Leroy Sane are set to freshen up the attack, but Bayern Munich starlet Jamal Musiala may be given a second bite at the cherry.
Matthias Ginter and Nico Schlotterbeck should also be in consideration for recalls to the backline alongside Antonio Rudiger, while Kevin Trapp and Marc-Andre ter Stegen have both been given the nod this month already, so it could very well be Bernd Leno's time to impress in between the sticks.
Germany possible starting lineup: Leno; Ginter, Rudiger, Schlotterbeck; Wolf, Gundogan, Goretzka, Gosens; Sane, Musiala; Fullkrug