diff --git a/go/pkg/pass1/cut-netspoc.go b/go/pkg/pass1/cut-netspoc.go
index 73b68d0a..31a7c6a7 100644
--- a/go/pkg/pass1/cut-netspoc.go
+++ b/go/pkg/pass1/cut-netspoc.go
@@ -576,7 +576,7 @@ func (c *spoc) cutNetspoc(
 
 	// Mark management_instance of routers
 	for _, r := range c.managedRouters {
-		if r.model.needManagementInstance {
+		if isUsed[r.name] && r.model.needManagementInstance {
 			if mr := c.getRouter(r.deviceName, r.ipV6); mr != nil {
 				for _, intf := range getIntf(mr) {
 					setIntfUsed(intf, isUsed)
diff --git a/go/testdata/cut-netspoc/cut-netspoc.t b/go/testdata/cut-netspoc/cut-netspoc.t
index 6328b3bf..26795085 100644
--- a/go/testdata/cut-netspoc/cut-netspoc.t
+++ b/go/testdata/cut-netspoc/cut-netspoc.t
@@ -3485,7 +3485,7 @@ service:s1 = {
 =END=
 
 ############################################################
-=TITLE=Retain management_instance
+=TITLE=Retain management_instance of used router
 =TEMPL=input
 network:n1 = { ip = 10.1.1.0/24; }
 network:n2 = { ip = 10.1.2.0/24; }
@@ -3516,4 +3516,25 @@ service:s1 = {
 [[input]]
 =OUTPUT=
 [[input]]
+=END=
+
+############################################################
+=TITLE=Ignore management_instance of unused router
+=INPUT=
+[[input]]
+router:r2 = {
+ model = NSX;
+ management_instance;
+ interface:n3 = { ip = 10.1.3.2; }
+}
+router:r2@v1 = {
+ model = NSX, T0;
+ managed;
+ routing = manual;
+ interface:n3 = { ip = 10.1.3.2; hardware = IN; }
+ interface:n4 = { ip = 10.1.4.1; hardware = OUT; }
+}
+network:n4 = { ip = 10.1.4.0/24; }
+=OUTPUT=
+[[input]]
 =END=
\ No newline at end of file