diff --git a/codes/models/SRGAN_model.py b/codes/models/SRGAN_model.py
index 9a141ab1..aa0fffb2 100644
--- a/codes/models/SRGAN_model.py
+++ b/codes/models/SRGAN_model.py
@@ -77,7 +77,7 @@ class SRGANModel(BaseModel):
         if self.is_train:
             self.netD = networks.define_D(opt).to(self.device)
             if self.spsr_enabled:
-                self.netD_grad = networks.define_D(opt).to(self.device)  # D_grad
+                self.netD_grad = networks.define_D(opt, wrap=True).to(self.device)  # D_grad
 
         if 'network_C' in opt.keys():
             self.netC = networks.define_G(opt, net_key='network_C').to(self.device)
diff --git a/codes/models/networks.py b/codes/models/networks.py
index deb26144..19387325 100644
--- a/codes/models/networks.py
+++ b/codes/models/networks.py
@@ -140,7 +140,15 @@ def define_G(opt, net_key='network_G', scale=None):
     return netG
 
 
-def define_D_net(opt_net, img_sz=None):
+class GradDiscWrapper(torch.nn.Module):
+    def __init__(self, m):
+        super(GradDiscWrapper, self).__init__()
+        self.m = m
+
+    def forward(self, x, lr):
+        return self.m(x, lr)
+
+def define_D_net(opt_net, img_sz=None, wrap=False):
     which_model = opt_net['which_model_D']
 
     if which_model == 'discriminator_vgg_128':
@@ -164,15 +172,17 @@ def define_D_net(opt_net, img_sz=None):
                                                     final_temperature_step=opt_net['final_temperature_step'])
     elif which_model == "cross_compare_vgg128":
         netD = SRGAN_arch.CrossCompareDiscriminator(in_nc=opt_net['in_nc'], ref_channels=opt_net['ref_channels'], nf=opt_net['nf'], scale=opt_net['scale'])
+        if wrap:
+            netD = GradDiscWrapper(netD)
     else:
         raise NotImplementedError('Discriminator model [{:s}] not recognized'.format(which_model))
     return netD
 
 # Discriminator
-def define_D(opt):
+def define_D(opt, wrap=False):
     img_sz = opt['datasets']['train']['target_size']
     opt_net = opt['network_D']
-    return define_D_net(opt_net, img_sz)
+    return define_D_net(opt_net, img_sz, wrap=wrap)
 
 def define_fixed_D(opt):
     # Note that this will not work with "old" VGG-style discriminators with dense blocks until the img_size parameter is added.