Juventus Risk Defensive Shake-Up as Galatasaray Pursue Two Serie A StarsTurkish champions Galatasaray remain confident of signing Juventus stalwart Gleison Bremer despite the players reservations. According to Gazzetta dello Sport, the Rams Park giants have already identified a suitable alternative should the Brazilian turn down a move to Istanbul.Gleison Bremer has emerged as Galatasarays top defensive target, with Juventus reportedly open to letting their best center-back leave this summer. Furthermore, Okan Buruks men have already tabled an eye-watering 8 million contract offer, hoping to persuade the former Torino man to continue his career in the Super Lig.However, the 29-year-old has been reluctant to accept Galatasarays proposal so far, insisting on staying at Juventus for at least another year. Bremers current contract runs until 2029, and theres little the Bianconeri can do to force him to join the Turkish outfit against his will.Aware of the situation, Galatasaray have set their sights elsewhere. Bologna star Jhon Lucumi has caught Buruks eye.Our take on Juventus & center-back carouselJuventus readiness to negotiate Bremers sale makes little sense, especially given his importance to the team. Yet, its worth noting that the Brazilian has recently struggled with injuries, and that could be the reason why theyre considering cashing in on him this summer.Meanwhile, Lucumi is ready to bid farewell to Bologna a year before his contract expires. At 28, he is an established Serie A defender at the peak of his powers, so Juventus interest feels natural. Still, whether hed be an upgrade on Bremer remains highly questionable.On top of that, Bologna value the Colombian at 25 million, a figure Juventus are unlikely to pay for a player who has less than 12 months left to run on his contract.