The report says Perch believes Murillo is more comfortable in a conventional central-defensive partnership, with a full-back outside him and a clearer zone to protect.
That changes in a back three. The left-sided centre-back must defend the channel, cover space behind the wing-back and step into wider areas when opponents attack the flank. It is a role that can expose hesitation, particularly when a player is still learning the distances and timing required by the system.
Perch summed up his view by saying: “Some formations suit certain players, and some don't. He's just finding his feet with it all.”
There is an important distinction between struggling with a role and lacking the quality to perform it. The report describes Perch as viewing Murillo as “excellent” in a back four, suggesting the concern is tactical rather than a judgment on his overall ability.
Murillo has reportedly continued to feature alongside Nikola Milenkovic in central defence, but Forest’s shape can ask him to defend much closer to the touchline. That creates more one-against-one situations and leaves less protection when possession is lost.
For Glasner, the challenge is finding enough stability without abandoning the principles of his preferred system. For Murillo, regular minutes could provide the clearest route to rebuilding confidence.
The report identifies Arsenal as Forest’s next Premier League test. It will be a demanding examination of Murillo’s positioning, especially against attackers capable of stretching the back line and exploiting the channels.
His Brazil prospects add another layer to the situation. The update says he has missed the most recent squad, meaning a return to international contention will likely depend on a sustained run of composed performances.
The Arsenal fixture should offer Murillo another chance to show that he can adapt to Glasner’s demands without losing the defensive aggression and composure that made him so highly regarded.